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BULLOUGH, W. S. 1960. Practical invertebrate anatomy. 2nd ed. London: Macmillan.

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FISCHER, P.-H., DuvAL, M. & Rarry, A. 1933. Etudes sur les échanges respiratoires des littorines. Archs

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Konn, A. J. 1960a. Ecological notes on Conus (Mollusca: Gastropoda) in the Trincomalee region of Ceylon.

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Koun, A. J. 19606. Spawning behaviour, egg masses and larval development in Conus from the Indian Ocean.

Bull. Bingham oceanogr. Coll. 17 (4): 1-51.

THIELE, J. 1910. Mollusca: B. Polyplacophora, Gastropoda marina, Bivalvia. In: SCHULTZE, L. Zoologische

und anthropologische Ergebnisse einer Forschungsreise im westlichen und zentralen Siid-Afrika 4: 269-270.

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(continued inside back cover)

ANNALS OF THE SOUTH AFRICAN MUSEUM

ANNALE VAN DIE SUID-AFRIKAANSE MUSEUM

Volume 72 ~~ #2Band

April 1977 April

Part 10 #£Deel

A SECOND ASSEMBLAGE OF PLIOCENE

INVERTEBRATE FOSSILS FROM

LANGEBAANWEG, CAPE

BRIAN KENSLEY

Cape Town Kaapstad

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A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE

FOSSILS FROM LANGEBAANWEG, CAPE

BRIAN KENSLEY

South African Museum, Cape Town

(With 16 figures)

[MS. accepted 30 November 1976]

ABSTRACT

An assemblage of fossils from the Quartzose Sand Member of the Varswater Formation

at Langebaanweg is described. The assemblage consists. of 20 species of gasteropods, 2 species

of bivalves, 1 amphineuran species, about 4 species of ostracodes, and the nucules of a species

of the alga Chara (stonewort). Included amongst the molluscs is a new species of Bullia, to

be described later by P. Nuttall of the British Museum, and a new species of the bivalve genus

Cuna described here. The molluscs represent a mixture of marine, marine/estuarine, estuarine,

freshwater, and terrestrial species. The ostracodes are all freshwater species. From the con-

dition and relative abundance of the fossils, it is suggested that the specimens were deposited

under very calm conditions in an estuarine area, perhaps after riverine flooding.

CONTENTS

PAGE

Introduction : : f 6 189

Systematic discussion : . 190

General discussion . é a PA0/

Acknowledgements . 5 oe 209

References . b : : 7209

INTRODUCTION

The commercial phosphate mine at Langebaanweg, Cape, has yielded a

vast array of fossils, mainly of Pliocene age (vide Hendey 1976). The fossils

are derived from the Varswater Formation, the geology of which is dealt with

in some detail by Tankard (19755). An assemblage of invertebrate fossils from

the Gravel Member of this formation has been described (Kensley 1972). This

Suite was composed mainly ‘of marine gasteropod and bivalve molluscs (both

fossil shells and shell casts) but also included a single brachiopod and echino-

derm, and barnacle fragments. Expansion of the quarrying activities has since

exposed a second assemblage of invertebrate fossils in the south-western part

of the mine. This material occurred in a mud deposit within the Quartzose

Sand Member, which immediately overlies the Gravel Member. These are the

fossils dealt with in the present report. All the material is housed in the South

African Museum, whose catalogue numbers they bear.

189

Ann. S. Afr. Mus. 72 (10), 1977: 189-210, 16 figs.

190 ANNALS OF THE SOUTH AFRICAN MUSEUM

SYSTEMATIC DISCUSSION

MOLLUSCA

Class GASTEROPODA

Family Trochidae

Gibbula benzi (Krauss)

Gibbula benzi: Barnard, 1963: 276.

Material

Single specimen, height 4,4 mm, width 5,0 mm.

Distribution

Living: East London to Saldanha.

Remarks

The colour pattern of white dots on the periphery, rows of dark and light

dots on the base, and the spire slightly mottled, is well preserved.

Oxystele variegata (Anton)

Oxystele variegata: Tankard, 1975a: 22.

Material

Single specimen, height 6,0 mm, width 10,0 mm.

Distribution

Living: Natal to southern Angola.

Fossil: Port Elizabeth, Verlorevlei, Saldanha.

Remarks

The general colour of the specimen is dark brown, but remains of the

colour pattern are still visible.

Family Phasianellidae

Tricolia capensis (Dunker)

Fig. 1

Tricolia capensis: Barnard, 1963: 206.

Material

Numerous specimens, from 1,6 mm to 4,0 mm in height.

Distribution

Living: False Bay to Kunene River mouth.

Remarks

All the specimens retain the characteristic colour pattern of a pale ground

with darker pink-brown spots and mottling.

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 19]

Fig. 1. Tricolia capensis (scale = 3 mm).

Tricolia neritina (Dunker)

Tricolia neritina: Kensley, 1972: 177.

Material

Two specimens, greatest diameter 3,4 mm, 2,0 mm.

Distribution

Living: East London to South West Africa.

Fossil: Langebaanweg.

Remarks

Both specimens retain the spiral colour bands of this species.

Family Littorinidae

Littorina cf. knysnaensis (Philippi)

Littorina knysnaensis: Tankard, 1975a: 22.

Material

Two damaged specimens, greatest diameter of larger specimen 5,0 mm.

Distribution

Living: Natal to Rocky Point, South West Africa.

Fossil: Saldanha, Verlorevlei, Knysna.

192 ANNALS OF THE SOUTH AFRICAN MUSEUM

Remarks

Both specimens are low-spired, showing about twenty-five spiral lines on

the body whorl, plus numerous fine growth lines characteristic of this species.

A basal keel as is found in specimens living in strong wave action, is not present.

Family Collumbellidae

Pyrene albuginosa (Reeve)

Fig. 2

Pyrene albuginosa: Barnard, 1962: 190.

Material

Thirteen specimens ranging in height from 3,5 mm to 7,4 mm.

Distribution

Living: Natal to False Bay.

Fossil: Port Elizabeth.

Remarks

Several of the specimens show two irregular rows of white spots on the

body whorl, white spots at the suture, and a darker reticulation between the

spots.

Fig. 2. Pyrene albuginosa (scale = 2 mm).

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 193

Family Nassariidae

Bullia digitalis (Meuschen)

Bullia digitalis: Barnard, 1959: 137.

Bullia sp. Kensley, 1972: 179.

Material

Ten specimens, all damaged, largest 20 mm length.

Distribution

Living: Port Elizabeth to Walvis Bay.

Fossil: Liideritz, Orange River, Langebaanweg, Keurbooms River.

Bullia laevissima (Gmelin)

Bullia laevissima: Tankard, 1975a: 23.

Material

Eight specimens, all damaged, length 6,0 mm to 21,0 mm.

Distribution

Living: Port Alfred to Walvis Bay.

Fossil: Bogenfels, Saldanha, Knysna.

Bullia sp.

Fig. 3

Remarks

Large numbers of this species varying in size from protoconch plus a few

postnatal whorls, to specimens up to 18 mm in length have been collected.

P. Nuttall of the British Museum is of the opinion that this is an undescribed

species and will be dealing with it in a later work.

Nassarius cf. analogicus (Sowerby)

Fig. 4

Nassa analogica: Barnard, 1959: 99.

Nassarius analogicus: Tankard, 1975a: 22.

Material

Three specimens, protoconchs missing, length 16,2 mm to 18,9 mm.

Distribution

Living: East London to St Helena Bay.

Fossil: Saldanha.

Remarks

Although the specimens are very worn, traces of the spiral lirae charac-

teristic of this variable species can be seen. Only faint traces of axial ribs are

visible on the upper whorls.

194 ANNALS OF THE SOUTH AFRICAN MUSEUM

Fig. 3. Bullia sp. (scale =5 mm).

Fig. 4. Nassarius cf. analogicus (scale = 4 mm).

Nassarius sp.

Fig. 5

Description

Protoconch smooth, 24 whorls; 2 postnatal whorls, first whorl with 14-15

axial ribs, second whorl with 14-15 ribs. First whorl with 5 spiral lirae, 6-7 on

second whorl, 4 on rostrum, 4-5 slightly stronger lirae on base.

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 195

Material

One damaged specimen, outer lip broken, length 3,3 mm, width 1,8 mm.

Remarks

The specimen agrees well with material of N. plebeja (Thiele) from Port

Elizabeth, and with Barnard’s (1959: 106) description. As this living species

has only been recorded from relatively deep water (80-100 metres) no certainty

can be placed on this identification.

Nassarius sp.

Fig. 6

Description

Protoconch plus 43 whorls, outer lip and base of shell damaged. Spire

tapering evenly, apical angle 45°. Axial ribs well separated bent slightly near

upper suture, and forming barely perceptible shoulder, 9-11 axial ribs per

whorl. Periphery of body whorl with single spiral lira stronger than other

faint lirae, latter almost obscure, about twelve per whorl.

Material

One specimen, damaged, length 15,5 mm width 7,0 mm.

Fig. 5. Nassarius sp. (scale | mm). Fig. 6. Nassarius sp. (scale = 2 mm).

196 ANNALS OF THE SOUTH AFRICAN MUSEUM

Remarks

The specimen closely resembles N. scopularcus, known as a Tertiary fossil

from Bogenfels, Saldanha, and taken alive from Langebaan and Liideritz, but

differs in the shape of the profile. N. scopularcus has a slightly convex profile,

as opposed to the present straight-sided specimen.

Family Marginellidae

Marginella sp.

Material

One specimen, length 2,9 mm.

Remarks

This species belongs to the group possessing a smoothly convex shoulder,

three columellar pleats. In general form there is some resemblance to

M. differens.

Family Assimineidae

Assiminea Sp.

Fig. 7

Material

Numerous specimens, length ranging from 2,4 mm to 4,0 mm.

Fig. 7. Assiminea sp. (scale 3 mm).

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 197

Remarks

In proportions this species resembles A. bifasciata but does not appear

to reach this species size. The present species is not quite as rounded and squat

as A. globulous, but falls within that species size range.

Family Ferrissiidae

Burnupia capensis (Walker)

Fig. 8

Burnupia capensis: Connolly, 1939: 521. Burch, 1975: 54.

Material

Numerous specimens, largest length 4,0 mm, width 2,3 mm.

Distribution

Living: Natal to southern Cape and Cape Peninsula.

Subfossil: from vlei deposit, Cape St Francis.

Remarks

As Burch (1975) has shown, the nature of the apical sculpture in the fresh-

water limpets is a very useful feature for separation of species. With this in

view, scanning electron micrographs were obtained of the present material.

These show the subapical rows of pits characteristic of B. capensis, but the

rows of pits are not as numerous as in the modern material figured by Burch.

The shape of the pits, however, is closer to B. capensis than to B. stenochorias

with its sparser pit rows. None of the present specimens reach the size of the

type or the fresh material in the South African Museum (i.e. up to 7,5 mm in

length) of B. capensis, which is itself a smaller species than a normal B. steno-

chorias (length 8,5 mm).

Family Planorbidae

Ceratophallus natalensis (Krauss)

Fig. 9

Planorbis natalensis Krauss, Connolly, 1939: 490.

Ceratophallus natalensis: Brown & Mandahl-Barth, 1973: 289.

Material

Numerous specimens, greatest diameter 4,7 mm.

Distribution

Living: eastern Africa from Eritrea to eastern Cape, westwards to Chad

and lower Congo.

Remarks

Connolly notes that populations of this species may for years remain below

the normal adult dimensions before reaching full size. This may account for

the small average size of the present material.

198 ANNALS OF THE SOUTH AFRICAN MUSEUM

Fig. 8. Burnupia capensis (scale = 1 mm) with electromicrograph enlargement of apex.

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 199

Fig. 9. Ceratophallus natalensis (scale = 2 mm).

Bulinus ‘tropicus’ (Krauss)

Fig. 10

Bulinus tropicus: Connolly, 1939: 499.

Material

Numerous specimens. Largest, length 3,9 mm, width 3,2 mm.

Distribution

Living: entire Republic of South Africa, Lesotho, Rhodesia, Botswana.

Subfossil: South West Africa.

Family Endodontidae

Trachycystis cf. capensis (Pfeiffer)

Fig. 11

Trachycystis capensis: Connolly, 1939: 228. Van Bruggen, 1970: 457.

Material

Seven specimens up to 4,2 mm width, 2,7 mm length.

Distribution

Living: East London to Orange River Mouth, common in coastal sand

dunes, seldom extending more than 24 km inland. Recorded from ‘Langebaan,

under stones in dry sand fields’ (Van Bruggen 1970: 458).

200 ANNALS OF THE SOUTH AFRICAN MUSEUM

Fig. 10. Bulinus ‘tropicus’ (scale 2mm).

Fig. 11. Trachycystis cf. capensis (scale 2 mm).

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 201

Family Succineidae

Succinea sp.

Fig. 12

Material

One specimen, length 3,3 mm, width 1,9 mm.

Remarks

In the relatively slender shape of the dextral shell, its very delicate structure,

this specimen resembles the genus Succinea. Without more material (and the

lack of soft parts) further identification is not possible.

Family Hydrobiidae

Tomichia ventricosa (Reeve)

Tomichia ventricosa: Connolly, 1939: 573.

Material

Two fragments.

Distribution

Living: southern Cape and Cape Peninsula.

Remarks

Although the material is fragmented, it agrees well with subfossil as well

as fresh material of this species.

Fig. 12. Succinea sp. (scale = 1 mm).

202 ANNALS OF THE SOUTH AFRICAN MUSEUM

? Family

Fig. 13

Material

Numerous shell apices, lower portion of shell never present, maximum

diameter 4,0 mm.

Remarks

There can be no certainty about the status of this species until a complete

specimen is found. The very flattened spire is similar to that of many of the

Naticidae. The rather delicate shell, however, is unlike most Natica species,

and the possibility that this is a freshwater or terrestrial species cannot be ruled

out.

Fig. 13. ? Family (scale 2 mm).

Class AMPHINEURA

Family Chitonidae

Chiton nigrovirescens (Blainville)

Fig. 14

Chiton nigrovirescens: Barnard, 1963: 342.

Material

Single valve, 11,5 mm wide.

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 203

Distribution

Living: False Bay to Liideritz.

Remarks

The single valve agrees exactly with a valve taken from a living animal,

in the shape of the apophyses, the ribbed lateral area and the pectinate margin

with its single slit.

Fig. 14. Chiton nigrovirescens (scale = 1 mm).

Class PELECYPODA

Family Donacidae

Donax serra (Réding)

Donax serra: Tankard, 1975a: 24.

Donax cf serra and Donax sp., Kensley, 1972: 183.

Material

Numerous fragments of left and right valve hinges, also several fragments

of the blade of the shell.

Distribution

Living: Kei Mouth to Walvis Bay.

Fossil: Angras Juntas, Oranjemund, Alexander Bay, Saldanha, Lange-

baanweg, Milnerton, Sedgefield.

Remarks

All the material is very fragmented, mainly hinge-lines surviving. Never-

theless, comparison with recent material of similar size shows no differences

in hinge structure, while the characteristic serrations of the lower margin of

this species are visible in some of the fragments.

Family Carditidae

Cuna aquaedulcensis sp. nov.

Fig. 15

Description

Valves inequilateral, umbo to anterior margin longer than umbo to pos-

terior margin length. Posterior margin straight. Sculpture consisting of 20-21

204 ANNALS OF THE SOUTH AFRICAN MUSEUM

radiating ribs crossed by numerous concentric growth lines, thus forming

elongate-rounded tubercles. Inner ventral margin crenulate, mantle line uninter-

rupted. Hinge line with anterior cardinal tooth elongate, low; posterior cardinal

tooth reduced to low knob. Median tooth relatively strong, narrowly triangular,

separated from anterior tooth by narrow gutter. Posterior tooth forming part

of shell margin. Single low lateral tooth on anterior margin.

Material

Holotype, right valve, length 3,4 mm, height 3,1 mm, SAM-L25892W.

Paratype, right valve, length 3,4 mm, height 3,1 mm, SAM-A25892W.

Fig. 15. Cuna aquaedulcensis (scale = | mm).

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 205

Remarks

This species most closely resembles the West African Cuna gambiensis

Nicklés, 1955. This similarity lies in the overall proportions, and in the external

sculpture. The West African species, however, has more radiating ribs (26)

than C. aquaedulcensis, while examination of the hinge lines shows obvious

differences. The right valve of C. gambiensis possesses three distinct cardinal

teeth, while the posterior cardinal tooth in the present species is reduced to a

knob. Little is known of the habits of these tiny bivalves. The specific name is

derived from the Varswater (freshwater) Formation in which it was found.

ARTHROPODA

Class CRUSTACEA

Subclass OSTRACODA

A vast number of perfect ostracode valves, often both valves together,

was obtained by sieving of the present sediments. Only about 5 species appear’

to be present, and of these 2 are abundant, the other 3 relatively uncommon.

Difficulty was experienced in identifying these latter; one is probably a Hetero-

cypris sp. There is little doubt, however, that the ostracodes are of freshwater

origin.

Family Cytheridae

Gomphocythere expansa (Sars)

Gomphocythere expansa: McKenzie, 1971: 162, 195.

Distribution

Living: known only from the Cape Flats.

Remarks

This is the most abundant ostracode in the sediments, and occurs in

thousands, often with the two valves joined. The very tumid shape and the

flattened ventral surface with its sharply marked ridge make this species quite

distinctive. Comparison with Sars’s type material revealed no differences from

the present material.

Family Cyprididae

Zonocypris cordata (Sars)

Zonocypris cordata: McKenzie, 1971: 169, 194.

Distribution

Living: vicinity of Cape Town, Port Elizabeth.

Remarks

This is the second most abundant species from the sediments, very often

occurring with both valves joined. Comparison with Sars’s type material

revealed no differences.

206 ANNALS OF THE SOUTH AFRICAN MUSEUM

CHAROPHYCOPHYTA (Stoneworts)

Chara sp.

Fig. 16

Material

Numerous nucules (2 sexual reproductive structures).

Remarks

In spite of their varying proportions, these nucules are all composed of

four spiral cells, thus placing the material in the genus Chara. R. D. Wood, of

the University of Rhode Island, U.S.A., who looked at the material, gave the

opinion that all the nucules belonged to the same species, variation in pro-

portions being quite usual. Without further structures, specific identification

is difficult. However, two possibilities present themselves:

Chara globularis a brackish water species usually living in water of a

salinity of 5-15%,.

Chara vulgaris a purely freshwater species.

This is the first record of a fossil alga from Langebaanweg. Previous plant

remains from the area include roots and pollen grains from the peat deposit,

as well as plant fragments (Hendey 1976: 243).

‘

Fig. 16. Nucules of Chara sp. (scale = 0,4 mm).

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 207

GENERAL DISCUSSION

As already mentioned, this assemblage of fossils was recovered from a

fine-grained horizon in the Quartzose Sand Member of the Varswater Forma-

tion. Speculation on the environmental conditions under which the animals

lived can be aided by two sources of information, viz. knowledge of the geology

of the area, and present-day ecological knowledge of the same or related species.

Regarding the geological evidence, Tankard (19755) has described the

broad series of events in the area, viz. a marine transgression in the Pliocene,

the accumulation of freshwater estuarine sands behind a barrier followed by a

final marine transgression. In the Quartzose Sand Member Tankard recognizes

in the sediments a fluviatile facies as well as an estuarine facies. A broad analysis

of the present fossil assemblage and what knowledge we have of the environ-

mental niches of these species, supports to some extent this geological view.

The fossils may be divided into the following categories:

MARINE SPECIES MARINE/ESTUARINE SPECIES

Bullia digitalis Bullia laevissima

Chiton nigrovirescens Littorina cf knysnaensis

Donas serra Marginella sp.

Gibbula benzi Nassarius spp.

Pyrene albuginosa Oxystele variegata

Tricolia capensis

Tricolia neritina

ESTUARINE SPECIES FRESHWATER SPECIES

Assiminea sp. Ceratophallus natalensis

Bulinus tropicus

Burnupia capensis

TERRESTRIAL SPECIES Chara sp.

Trachycystis capensis Gomphocythere expansa

Succinea sp.

Tomichia ventricosa

Zonocypris cordata

Under the marine/estuarine group are included species which have been

recorded in both habitat types, as well as those forms which are only tentatively

identified, and whose genera are usually marine, but sometimes also estuarine,

e.g. Nassarius.

The assemblage is thus obviously a mixture of species from a variety of

habitats, with major contributions from the marine and the freshwater repre-

sentatives. If the assemblage is looked at in terms of abundance (even though

208 ANNALS OF THE SOUTH AFRICAN MUSEUM

no quantitative collecting as such was done), it becomes apparent that a few

species are very common, the rest being rare. These abundant species are the

following: ;

MARINE SPECIES FRESHWATER SPECIES

Tricolia capensis Ceratophallus natalensis

Bulinus tropicus

Burnupia capensis

Gomphocythere expansa

Zonocypris cordata

The new species of Bullia is probably not a freshwater species, but whether

it is purely marine or marine/estuarine, is uncertain. The abundance of all

stages of these Bullia shells, and their good state of preservation, however,

suggests that this was an estuarine species.

To speculate on the environmental conditions at the time of deposition,

not only the species composition (and their ecological implications) must be

considered, but also the sediments and the state of preservation of the fossils.

The following points are of relevance in this connection: the sediments are very

fine with a considerable clay fraction; many of the ostracodes are undamaged

and often both valves are still joined; the nucules of Chara are often complete,

in spite of the very delicate and brittle nature of the spiral cells; Bulinus, Bur-

nupia, and Ceratophallus are small, very delicate shells, yet the majority of

specimens are undamaged. Deposition must thus have taken place under very

calm conditions.

To explain the presence of marine, estuarine, and freshwater species in

the sediments, one must postulate a lagoonal/estuarine area, protected from

wave action, yet with access to the sea. Close to this sea-mouth, there must

have been both rocky shores (to accommodate Tricolia, Pyrene, Oxystele,

and Chiton), and sandy shores (Donax, Bullia digitalis). Tidal movement could

wash these marine forms into the sheltered lagoon, the larger shells such as

Donax and Bullia becoming abraded and fragmented, the smaller shells of

Pyrene and Tricolia surviving intact. (Movement of shells of the two former

genera into a lagoon from the sea has been observed by the author at Milnerton.)

That the rocky shores were nearby is implied from the condition of the Pyrene

and Tricolia shells. These are without exception unworn, with the protoconches

preserved, and in most cases, the colour patterns still visible. The true estuarine

forms could have lived along the lagoonal/estuarine shores (Assiminea sp.) or

on the muddy bottom (Bullia laevissima). The Charophyte alga probably

flourished in a pond or temporary pool, isolated from the general estuary (as

shown in Hendey 1976, fig. 2). (Charophytes, which are abundant on the

present-day Cape Flats, are usually found in quiet ponds, shallow water holes,

temporary pools, and dams (Stephens 1929).) The large numbers of fluviatile

molluscs and ostracodes might have been washed in by seasonal floods, with

the flood waters sweeping over nearby stagnant pools, finally to loose their

A SECOND ASSEMBLAGE OF PLIOCENE INVERTEBRATE FOSSILS 209

force and spread out in the lagoonal/estuarine area. Fine sediment in suspension,

as well as the mollusc and ostracode shells and the charophyte nucules would

then settle on the bottom, along with the marine/estuarine shells already there.

Deposition of these sediments occurred during a stillstand in a marine trans-

gression (Tankard 19755: 271).

The presence of the terrestrial Trachycystis can also be explained by

flooding, or by strong wind action.

Comparison between the present fossil suite and the assemblage previously

recorded from the Gravel Member of the same formation, shows that only

two species occur in both. These are Bullia digitalis and Donax serra, both

marine sand-dwelling species, still occurring on the nearby coast at Saldanha.

The general dissimilarity is not surprising in view of the fact that the Gravel

Member material was evidently accumulated in a marine beach environment.

The differences between the two assemblages do not necessarily have any

temporal significance.

ACKNOWLEDGEMENTS

I am grateful to Mr C. Appleton, Mr R. N. Kilburn, and Dr A. J. Tankard

for reading the manuscript and for their useful criticisms; to Dr Q. B. Hendey

for comments and for making the material available; to Prof. R. D. Wood of

the University of Rhode Island, U.S.A., for his comments on the Charophytes;

to Mr D. Gerneke for the photographs, and to Dr Tankard for arranging for

the electromicrographs to be taken at Rhodes University, Grahamstown.

REFERENCES

BARNARD, K. H. 1959. Contributions to the knowledge of South African marine Mollusca.

Part II. Gastropoda: Prosobranchiata: Rhachiglossa.— Ann. S. Afr. Mus. 45: 1-237.

BARNARD, K. H. 1962. Revised list of South African Late Tertiary and Pleistocene marine

Mollusca.— Trans. R. Soc. S. Afr. 36: 179-196.

BARNARD, K. H. 1963. Contributions to the knowledge of South African marine Mollusca.

Part IV. Gastropoda: Prosobranchiata: Rhipidoglossa, Docoglossa. Tectibranchiata.

Polyplacophora. Solenogastres. Scaphopoda.— Amn. S. Afr. Mus. 47: 201-360.

Brown, D. S. & MANDAHL-BARTH, G. 1973. Two new genera of Planorbidae from Africa

and Madagascar.— Proc. malac. Soc. Lond. 40: 287-302.

Burcu, J. B. 1975. Apical shell sculpture of some African freshwater limpets (Mollusca:

Basommatophora: Ancylidae).— Zool. afr. 10: 53-62.

CONNOLLY, M. 1939. A monographic survey of South African non-marine Mollusca.— Ann.

S. Afr. Mus. 33: 1-660.

HENDEY, Q. B. 1976. The Pliocene fossil occurrences in ‘E’ Quarry, Langebaanweg, South

Africa.— Ann. S. Afr. Mus. 69: 215-247.

KENSLEY, B. F. 1972. Pliocene marine invertebrates from Langebaanweg, Cape Province.

—Ann. S. Afr. Mus. 60: 173-190.

McKenzie, K. G. 1971. Species list of South African freshwater Ostracoda with an appendix

‘listing museum collections and some further determinations.— Ann. S. Afr. Mus. 57:

157-213.

NICKLEs, M. 1955. Scaphopodes et lamellibranches récoltés dans l'Ouest africain. — Atlantide

Rep. 3: 93-238.

210 ANNALS OF THE SOUTH AFRICAN MUSEUM

STEPHENS, E. L. 1929. Fresh water aquatic vegetation of the south-western districts. In:

ADAMSON, R. S., et al., eds. The Botanical features of the south-western Cape Province.

Cape Town: Speciality Press.

TANKARD, A. J. 1975a. Thermally anomalous Late Pleistocene molluscs from the south

western Cape Province, South Africa.— Ann. S. Afr. Mus. 69: 17-45.

TANKARD, A. J. 19755. Varswater Formation of the Langebaanweg-Saldanha area, Cape

Province.— Trans. geol. Soc. S. Afr. 77: 265-283.

VAN BRUGGEN, A. C. 1970. Non Marine Mollusca. Jn: HANSTROM, B., BRINCK, P., & RUDE-

BECK, G., eds. South African animal life 14: 444-476. Lund: Berlingska Boktryckeriet.

6. SYSTEMATIC papers must conform with the International code of zoological nomenclature

(particularly Articles 22 and 51).

Names of new taxa, combinations, synonyms, etc., when used for the first time, must be

followed by the appropriate Latin (not English) abbreviation, e.g. gen. NOv., sp. nov., comb.

nov., Syn. nov., etc.

‘An author’s name when cited must follow the name of the taxon without intervening

punctuation and not be abbreviated; if the year is added, a comma must separate author’s

name and year. The author’s name ‘(and date, if cited) must be placed in parentheses if a

species or subspecies is transferred from its original genus. The name of a subsequent user of

a scientific name must be separated from the scientific name by a colon.

Synonymy arrangement should be according to chronology of names, i.e. all published

scientific names by which the species previously has been designated are listed in chronological

order, with all references to that name following in chronological order, e.g.:

Family Nuculanidae

Nuculana (Lembulus) bicuspidata (Gould, 1845)

Figs 14-15A

Nucula (Leda) bicuspidata Gould, 1845: 37.

Leda plicifera A. Adams, 1856: 50.

Laeda bicuspidata Hanley, 1859: 118, pl. 228 (fig. 73). Sowerby, 1871: pl. 2 (figs 8a—b).

Nucula largillierti Philippi, 1861: 87.

Leda bicuspidata: Nicklés, 1950: 163, fig. 301; 1955: 110. Barnard, 1964: 234, figs 8-9.

Note punctuation in the above example:

comma separates author’s name and year

semicolon separates more than one reference by the same author

full stop separates references by different authors

figures of plates are enclosed in parentheses to distinguish them from text-figures

dash, not comma, separates consecutive numbers

Synonymy arrangement according to chronology of bibliographic references, whereby

the year is placed in front of each entry, and the synonym repeated in full for each entry, is

not acceptable.

In describing new species, one specimen must be designated as the holotype; other speci-

mens mentioned in the original description are to be designated paratypes; additional material

not regarded as paratypes should be listed separately. The complete data (registration number,

depository, description of specimen, locality, collector, date) of the holotype and paratypes

must be recorded, e.g.:

Holotype

SAM-A13535 in the South African Museum, Cape Town. Adult female from mid-tide region, King’s Beach,

Port Elizabeth (33°51’S 25°39’E), collected by A. Smith, 15 January 1973.

Note standard form of writing South African Museum registration numbers and date.

7. SPECIAL HOUSE RULES

Capital initial letters

(a) The Figures, Maps and Tables of the paper when referred to in the text

OE . the Figure depicting C. namacolus . . in C. namacolus (Fig. 10) .

(b) The aes of prefixed surnames in all neaiees ene used in the text, if not Oe

by initials or full names

e.g. DuToit but A.L.du Toit; Von Huene but F. von Huene

e.g. Therocephalia, but therocephalian

Punctuation should be loose, omitting all not strictly necessary

Reference to the author should be expressed in the third person

Roman numerals should be converted to arabic, except when forming part of the title of a

book or article, such as

‘Revision of the Crustacea. Part VIII. The Amphipoda.’

Specific name must not stand alone, but be preceded by the generic name or its abbreviation

to initial capital letter, provided the same generic name is used consecutively.

Name of new genus or species is not to be included in the title: it should be included in the

abstract, counter to Recommendation 23 of the Code, to meet the requirements of

Biological Abstracts.