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ANNALS OF THE SOUTH AFRICAN MUSEUM
ANNALE VAN DIE SUID-AFRIKAANSE MUSEUM

Volume 72 # Band
November 1976 November
Part 4 Deel

GALESPH YRUS CAPENSIS,
A YOUNGINID EOSUCHIAN FROM
me CISTECEPHALUS ZONE OF SOUTH AFRICA

By

ROBERT L. CARROLL

Cape Town Kaapstad

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GALESPHYRUS CAPENSIS, A YOUNGINID EOSUCHIAN FROM
THE CISTECEPHALUS ZONE OF SOUTH AFRICA

By

ROBERT L. CARROLL
Redpath Museum, McGill University, Montreal, Canada

(With 3 figures)
LMS accepted 5 May 1976]

ABSTRACT

Galesphyrus capensis, a primitive eosuchian reptile, is represented by two partial skeletons
from the Cistecephalus zone of South Africa. Little is known of the skull. The teeth are smaller
and more numerous than those of Youngina from the overlying Daptocephalus zone. Postcranial
features of the skeleton are similar in the two genera, although the metatarsals are relatively
longer in Youngina. The tarsus of Galesphyrus is very well preserved, providing a basis for
comparison with those of more advanced diapsids. Neither of these younginid genera appear
to be closely related to the Upper Pennsylvanian diapsid Petrolacosaurus, and may represent
a distinct line of persistently small forms.

CONTENTS
PAGE
Introduction 3 5 : 5 é : 59
Description
Skull and lower jaw . : q : 62
Vertebrae . : : 5 : : 62
Ribs : ; : ; ; i 64
Pectoral girdle and limb . f : 64
Pelvic girdle and limb ; : : 65
Discussion . ; : : ; 5 ; 67
Acknowledgements. : ; : ; 68
References . : 5 ? ‘ : E 68
INTRODUCTION

Reptiles first appear in the fossil record in the early Upper Carboniferous.
Primitive groups remain dominant through the Lower Permian. Early members
of all the living orders (Chelonia, Crocodilia, Squamata and Rhynchocephalia)
are known by the late Triassic. Little specific evidence is yet available linking
the advanced reptiles with their Palaeozoic predecessors. A number of forms
from the Upper Permian and Lower Triassic, collectively termed eosuchians, has
long been felt to represent an intermediate level of reptilian evolution. Eosuchians
are generally accepted as being ancestral to lizards and rhynchocephalians, and
have frequently been suggested as being ancestral to the archosaurs as well.
Despite their significance, much remains to be learned of the anatomy and
phylogeny of eosuchians.

The earliest diapsid, and so apparently the oldest recognizable ancestor of

Sy)

Ann. S. Afr. Mus. 72 (4), 1976: 59-68, 3 figs.

60 ANNALS OF THE SOUTH AFRICAN MUSEUM

the eosuchians, is Petrolacosaurus (Reisz 1975) from the Upper Pennsylvanian
of North America. Aside from the configuration of the temporal region,
Petrolacosaurus is quite primitive in cranial morphology, but rather specialized
in the nature of the limbs and girdles. It is not obviously closely related to any
of the known Upper Permian or Lower Triassic genera. For information on the
differentiation of the advanced reptilian orders, more knowledge of middle and
late Permian genera is necessary.

The family Younginidae has long been considered central to the eosuchian
concept (Broom 19146; Watson 1957; Romer 1966). Descriptions of the skull
and postcranial skeleton of Youngina have recently been published (Gow 1975).
This work goes far toward establishing the general proportions of late Permian
eosuchians. Unfortunately, anatomical details of many of the elements appear
poorly preserved, so that supplemental information would be desirable. All the
known specimens of Youngina come from the Daptocephalus zone (Kitching
1970) at the top of the South African Permian. Since both archosaurs (Hughes
1963) and fairly advanced lizard-like genera (Carroll 1975) occur in the same
or equivalent horizons, it is important to learn more of earlier eosuchians.

In 1914, Broom (1914a) described as the type of a new therapsid species,
Galesphyrus capensis, a specimen in the South African Museum, SAM-—2758,
collected from Oorlog’s Kloof, Calvinia, Cape Province. Romer (1956) sub-
sequently included this species among the Younginidae. According to J. W.
Kitching (pers. comm.), this specimen comes from the base of the Cistecephalus
zone, considerably below the horizon from which Youngina is known. The
specimen (Fig. 1) consists of most of a skeleton except the skull, preserved
primarily as an impression of the dorsal surface in a water-worn cobble of fine-
grained sandstone. Some of the remaining bone was removed with hydrochloric
acid, but this technique appeared to be weakening the surface of the block and
sO was terminated prior to complete removal of the vertebral column. The
resultant mould was cast with liquid latex. Where acid preparation was com-
pleted, excellent surface detail is evident. This is particularly important in the
area of the carpus and tarsus.

A second eosuchian specimen, also from the Cistecephalus zone, may pertain
to Galesphyrus. It is a partial skeleton in the collection of the Bernard Price
Institute (No. 4286), from Meerderyk, Colesberg, Cape Province (Fig. 2). It also
is preserved as a natural cast, in a small block of rather coarse sandstone. It
includes part of the lower jaw, a large fragment of the maxilla, much of the
vertebral column and ribs and elements of both girdles and limbs.

Identification of this material as belonging to the Younginidae is based on
comparison with Youngina from the overlying Daptocephalus zone. In as far as
comparable elements are present, there is little to differentiate the specimens
from the two horizons, except for the larger number and smaller size of the
maxillary teeth in the older form, and the relatively greater length of the meta-
tarsals in Youngina. The vertebrae are similar in having short neural spines, with
the zygapophyses widely spaced and relatively flat, as in the captorhinomorph

GALESPHYRUS CAPENSIS, A YOUNGINID EOSUCHIAN FROM SOUTH AFRICA 61

Fig. 1. Galesphyrus capensis, type, South African Museum 2758; Oorlog’s Kloof, Calvinia,

Cape Province; » 1,5. Abbreviations: a, astragalus; cal,calcaneum; cen, centrale; cl, clavicle;

i, intermedium; lc, lateral centrale; mc, medial centrale; p, pisiform; r, radiale: sc, scapula;
u, ulnare; 1, 2, 3, 4, 5, distal carpals and tarsals.

62 ANNALS OF THE SOUTH AFRICAN MUSEUM

Captorhinus. There is no evidence of dermal armour associated with the vertebrae
of Galesphyrus, as has been described in the more specialized eosuchian Heleo-
saurus, also from the Cistecephalus zone (Carroll 1976). Isolated armour plates
have been recognized in Youngina (Gow 1975).

Relatively little of the skeleton is preserved in both specimens of Galesphyrus.
Their identity is based primarily on overall similarity in size and proportions,
and particularly the similarity of vertebral structure. Although both specimens
are rather incomplete and their specific identity subject to some question, the
extreme rarity of eosuchians from this horizon makes it worth while to publish
a complete description. It is of particular importance to document the structure
of the tarsus because of the very important changes in foot structure that occur
in the many derived diapsid lines during the Triassic.

DESCRIPTION
SKULL AND LOWER JAW

The only cranial remain is the right maxilla, lacking the anterior portion,
in the Bernard Price Institute specimen. Eight blunt, peg-like teeth can be seen,
with room for at least four more in this segment of the bone. Relative to the
size of the maxilla, the teeth are smaller and more numerous than those of
Youngina capensis. Unlike the teeth in that genus, they are not recurved. The
associated lower jaw shows the dorsal posterior margin of the dentary.

VERTEBRAE

In the South African Museum specimen, 22 vertebrae are present in articu-
lation anterior to the sacrum. The eosuchian He/eosaurus, from the same horizon,
has 25 presacral vertebrae, suggesting that approximately 3 are missing in this
specimen. There are 2 sacrals and 8 caudals in sequence. Three additional
caudals can be seen adjacent to the 15th—17th trunk vertebrae. Presumably the
tail curved around most of the body. The observed caudals may not be at the
very end of the tail, but the tail was apparently at least twice the length of the
trunk region. The cervical and trunk vertebrae have widely spaced zygapophyses,
giving the neural arches an appearance closely comparable to those of Youngina
described by Watson (1957, fig. 20). This is in strong contrast to the medially
placed, sharply tilted zygapophyses of the dromosaurs, with which Broom had
originally allied this species. The neural spines are short and roughly triangular
in lateral view. Those in the anterior portion of the column, particularly vertebrae
9 and 11 (assuming only three cervicals are missing), are expanded laterally and
flattened at the top. Presumably, such specialization would serve to strengthen
the column, as would the dermal scutes of thecodonts and Heleosaurus. The
transverse processes are short and angle anteroventrally from the anterior
portion of the pedicle. Where the arches have not been prepared, the neural
canal is exposed dorsally. The ventral and lateral margins are essentially flat.
There are two sacral vertebrae: as exposed, they are not distinguishable from
those of the posterior trunk except by the larger size of the transverse processes.

GALESPHYRUS CAPENSIS, A YOUNGINID EOSUCHIAN FROM SOUTH AFRICA 63

Fig. 2. Galesphyrus capensis, Bernard Price Institute 4286; Meerderyk, Colesberg, Cape
Province; «1,5. Jaws were oriented at right angles to the plane of the remainder of the skeleton;
they are illustrated to the left of the skeleton to save space.

64 ANNALS OF THE SOUTH AFRICAN MUSEUM

Behind the sacrum, the neural arches narrow rapidly, with the zygapophyses
approaching the midline. The first six bear well-developed transverse processes.
The most distal caudals visible have very long, narrow, notochordal centra with
closely integrated and very much abbreviated neural arches.

Because of the manner of preservation, neither haemal arches nor trunk
intercentra are exposed. In dorsal view, the trunk centra can be seen to fit closely.
Presumably, as in other eosuchians, they were deeply notochordal.

RIBS

Ribs are present from the fourth (the most anteriorly preserved) vertebra
posteriorly. The most anterior appears considerably shorter than those succeed-
ing it. On this basis it may be considered a cervical. The fifth rib resembles those
more posterior. The trunk ribs have long narrow shafts, and at least the more
anterior have clearly separate tubercular and capitular heads. The length remains
constant to the sixteenth, and then decreases rapidly. Only fragments of ribs
21-25 are visible. There are two pairs of sacral ribs, suturally attached rather
than fused to the transverse processes. They apparently had distinct capitular
heads as well, but this area is incompletely exposed. The end of each rib expands
ventrally as well as anteriorly and posteriorly from a constricted shaft to form
a large surface for articulating with the ilrum. The first six caudal vertebrae have
short ribs which, like the sacrals, are suturally attached rather than fused to the
vertebrae. They extend straight out from the pedicle, rather than extending
posteriorly, as in captorhinomorph cotylosaurs and Petrolacosaurus. The length
of the last three diminishes rapidly.

PECTORAL GIRDLE AND LIMB

Of the shoulder girdle, only the dorsal portion of the right clavicular stem
and the scapulocoracoid are visible. What little there is is comparable to this
region in other primitive reptiles, but does not permit more specific comparison.
No cleithrum is visible, although remains would be expected in an animal
preserved in this manner if the element were originally present.

Most of the right humerus is visible in more or less its normal position.
As in other small primitive reptiles, the ends are expanded to an approximately
equal extent and set at a considerable angle to one another. Neither articulating
surface is well exposed. Not even the presence of the entepicondylar foramen
can be established. The bone is equal in length to approximately four trunk
vertebrae. The radius and ulna, of approximately equal length (80°% that of the
humerus), have fairly simple, lightly built shafts, with the two ends of both
expanded to an approximately equal extent. The ulna is distinguished by the
presence of a number of grooves and ridges on the posterior margin just beneath
the area where the olecranon might have developed. Comparisons of limb propor-
tions with those of Youngina capensis are indicated in Table I. The humerus is
longer, relative to the femur in Galesphyrus, but shorter, relative to the ulna
and radius.

GALESPHYRUS CAPENSIS, A YOUNGINID EOSUCHIAN FROM SOUTH AFRICA 65

TABLE |
r t H
H r u H Ie t f 1 Ie
Youngina capensis 23 18 Ky Wey 3y! 68%
Galesphyrus capensis 21 17 LOS5 2817, 27, 25 PAs EID aks,

TABLE I. Limb measurements and proportions of Galesphyrus and Youngina, in mm.
Measurements of Youngina courtesy of C. E. Gow, based on Bernard Price Institute specimen
3859. Galesphyrus measurements based on South African Museum specimen 2758.
H—humerus; r—radius; u—ulna; F—femur; t—tibia; f—fibula.

The carpals are preserved in almost normal articulation, although the lateral
margin of the area was weathered somewhat prior to discovery, resulting in the
loss of the fifth distal carpal, the lateral margin of the ulnare and most of the
pisiform. The configuration of the carpus is generally similar to that of the
captorhinomorph Paleothyris (Carroll 1969). The only conspicuous difference
is the simpler pattern of the intermedium, without a sharp constriction between
the area of ulnar and radial articulation. Of the hand, only the proximal ends
of metacarpals 2 and 3 are visible. The carpus of Youngina (Gow 1975) is not
sufficiently well preserved for detailed comparison.

In the earliest diapsid, Petrolacosaurus, the ulnare and intermedium are
much longer bones than in either Galesphyrus or captorhinomorphs, presumably
in relationship to the greater length of the ulna and radius. The proximo-distal
length of the entire carpus is reduced in the ancestors of squamates, but remains
long in crocodiles.

PELVIC GIRDLE AND LIMB

Only the dorsal portion of the pelvis is exposed in the South African Museum
specimen. Most of the rather narrow iliac blades are visible, but only the dorsal
rim of the acetabulum and the dorsal portion of the left pubis are preserved.
In the Bernard Price Institute specimen, the anterior portion of the pelvic girdle
can be seen in mediodorsal view. The anterior margin of the pubis is quite
thick, with an anteriorly facing pubic tubercle, and an opening for the
obturator foramen adjacent to the base of the ilium. The pubis appears to be
recessed posteriorly for a thyroid fenestra, but this is probably an artefact of
preservation. The apparent posterior margins are not smooth or symmetrical
on the two sides. It is probable that the posterior portion has been weathered
away, or had been slow to ossify. Only fragments of the ischia are preserved. The
blade of the ilium is in the shape of a narrow rectangle, ending abruptly
distally. The medial surface shows areas for the attachment of two sacral ribs.

Both femora are preserved in the South African Museum specimen, but
little can be seen of the ventral surface which would be expected to show the most
diagnostic features. The head appears to occupy the entire proximal surface of
the bone, as in most other primitive reptiles, but in strong contrast to the con-

66 ANNALS OF THE SOUTH AFRICAN MUSEUM

temporary eosuchian Heleosaurus. The shaft is approximately the length of five
trunk vertebrae. The tibia and fibula are relatively much longer and more robust
than their counterparts in the forelimb. The distal end of the tibia is relatively
much larger than that of the captorhinomorph Paleothyris, suggesting firmer
union with the astragalus. Petrolacosaurus shows a pattern similar to that of
Galesphyrus. The fibula is somewhat longer than the tibia. The proximal end is
not well exposed on either side but can be seen to be roughly cylindrical. The
distal end is flattened and expanded in the same plane as the tarsals and would
have articulated equally with the astragalus and calcaneum.

The tarsals are well exposed. In both feet they are visible dorsally. The
pattern and relative position of the elements are broadly similar to those of
primitive captorhinomorphs and pelycosaurs. The large astragalus bears facets
for both the tibia and fibula, separated by a notch. This bone is clearly a unitary
structure, but presumably it developed, as did that of Captorhinus (Peabody
1951), from primitively separate tibiale, intermedium and proximal centrale. The
calcaneum, with the astragalus, forms the margin of the perforating foramen,
and supports the fibula. Below the astragalus is a single, large, triangular centrale.
There are five distal tarsals. The fourth is the largest and supports both the
astragalus and calcaneum. The fifth is the smallest, a tiny oval bone, apparently
not as wide as the proximal end of the fifth metatarsal. The surface of the fifth
distal tarsal is completely unfinished bone, indicating very free movement of the
fifth digit. Although it may normally have assumed a divergent position, all the
digits are closely aligned on both sides in this specimen. The proximo-medial
border of the first distal tarsal is missing, but this bone probably had an oval
outline. The second and third are somewhat interlocked and may have functioned
as a unit. The metatarsals follow the pattern of captorhinomorphs in increasing
their length from the first to the fourth, with the fifth slightly shorter than the

Fig. 3. Tarsus of primitive eosuchians. A. Petrolacosaurus, Upper Pennsylvanian of Kansas,
x1 (from Reisz 1975). B. Galesphyrus, Cistecephalus zone, South Africa; * 1,5. C. Youngina,
Daptocephalus zone, South Africa; 1,5 (from Broom 1921).

GALESPHYRUS CAPENSIS, A YOUNGINID EOSUCHIAN FROM SOUTH AFRICA 67

third. The fifth shows no evidence of incipient hooking. The entire tarsus appears
essentially flat, as that of romeriids and captorhinids.

Comparison with the romeriid Paleothyris, in which the foot is well known,
shows several differences. The astragalus and calcaneum are somewhat smaller
relative to the distal elements in Galesphyrus. In Paleothyris, there is a small
medial centrale that is lost in Galesphyrus, and the lateral centrale is more
elongate. The fifth distal tarsal is relatively smaller in the latter form.

The tarsus of Petrolacosaurus (Fig. 3A) is generally similar to that of
Galesphyrus, except for the relatively larger size of the proximal elements. This
feature is a primitive characteristic, common also to pelycosaurs. The astragalus
and calcaneum are closely integrated in Petrolacosaurus, but may have become
more movable relative to each other in Galesphyrus. The centrale is larger in
Galesphyrus and may have been more closely integrated with the astragalus, a
tendency that is emphasized in some later diapsids, particularly the
squamates.

The tarsus of Youngina (Fig. 3C) has been described by Broom (1921) and
Goodrich (1942), but this material can no longer be located. Broom’s reconstruc-
tion (1921, fig. 20) shows the centrale (identified by Broom as a tibiale) as a
narrow oblong element, but his specimen drawing (Fig. 19) shows an oval shape
comparable to that of Galesphyrus. In as far as can be judged from these illustra-
tions, the arrangement and configuration of the bones are essentially similar in
the two genera. The metatarsals are substantially longer, relative to the tarsus,
in Youngina. Broom restores the fifth metatarsal in Youngina as slightly longer
than the third. In Galesphyrus the fifth is slightly shorter.

No dermal scales are associated with either specimen of Galesphyrus.

DISCUSSION

Galesphyrus was a small primitive eosuchian resembling Youngina in most
features of the skeleton. It is more advanced than Petro/acosaurus in having the
proximal caudal ribs extending directly laterally, rather than posteriorly, and in
the reduction of the relative size of the proximal tarsals.

The structure and proportions of the limbs and vertebrae are less specialized
than those of Petrolacosaurus, possibly because of the smaller size of Galesphyrus,
assuming these specimens are near to adult size as is suggested by the high
degree of ossification of carpus and tarsus.

Aside from Youngina, Galesphyrus shows no specific affinities with other
eosuchians, or any of the more specialized, derived diapsid lineages. These two
genera may represent a persistently primitive group of generalized habits, from
which, at a somewhat earlier time, the more specialized eosuchian families arose.
Close affinities with the earliest known diapsid, Petrolacosaurus, are not apparent.
Since the two genera are separated by the length of an entire geological period,
one might postulate a considerable remodelling of the skeleton to produce the
pattern of the postcranial skeleton evident in Galesphyrus, perhaps related to the

68 ANNALS OF THE SOUTH AFRICAN MUSEUM

smaller size of the latter form. It might also be argued that Galesphyrus had
evolved from a separate lineage of eosuchians, already distinct in the Upper
Carboniferous, which had remained more primitive in its postcranial anatomy
in relationship to a persistently smaller body size.

ACKNOWLEDGEMENTS

I wish to thank Dr T. H. Barry and Dr Michael Cluver for their hospitality
and assistance while this work was being carried out in the South African
Museum, where | had the opportunity to utilize the splendid collections
assembled by Broom, Haughton and Boonstra. Mr N. J. Eden provided technical
assistance in preparing and casting these and other specimens.

I also wish to express my appreciation to Drs Cruickshank and Gow for
their assistance in making facilities available at the Bernard Price Institute in
Johannesburg. Dr Kitching was extremely helpful in providing stratigraphic
data on these and other specimens from South Africa, and for introducing me
to collecting in the Karoo.

This work was supported by grants from the Merrill Foundation, the
National Research Council of Canada and the Faculty of Graduate Studies and
Research, McGill University.

REFERENCES

Broom, R. 1914a. Croonian lecture: On the origin of mammals.— Phil. Trans. R. Soc. Lond.
(B) 206: 1-48.

Broom, R. 19145. A new thecodont reptile.— Proc. zool. Soc. Lond. 1914: 1072-1077.

Broom, R. 1921. On the structure of the reptilian tarsus.— Proc. zool. Soc. Lond. 1: 143-155.

CARROLL, R. 1969. A Middle Pennsylvanian captorhinomorph, and the interrelationships of
primitive reptiles.—J. Paleont. 43: 151-170.

CARROLL, R. 1975. Permo-Triassic ‘lizards’ from the Karroo.—Palaeont. afr. 18: 71-87.

CARROLL, R. 1976. Eosuchians and the origin of archosaurs. Jn: CHURCHER, C. S., ed. Athlon:
Essays on palaeontology in honour of Loris Shano Russell. Misc. Publ. R. Ont. Mus.: 58-79.

GoopricH, E. S. 1942. The hind foot in Youngina and fifth metatarsal in Reptilia.—J. Anat.
76: 308-312.

Gow, C. 1975. The morphology and relationships of Youngina capensis Broom and Prolacerta
broomi Parrington.—Palaeont. afr. 18: 89-131.

HuGues, B. 1963. The earliest archosaurian reptiles.—S. Afr. J. Sci. 59: 221-241.

KitcHIna, J. W. 1970. A short review of the Beaufort zoning in South Africa. In: Proceedings
and papers: Second Gondwana Symposium: 309-312. Pretoria: Council for Scientific and
Industrial Research.

PEABopy, F. 1951. The origin of the astragalus of reptiles.— Evolution 5: 339-344.

Resz, R. 1975. Petrolacosaurus kansensis Lane: the earliest known diapsid reptile. Unpublished
Ph.D. thesis, McGill University, Dept. of Biology.

Romer, A. S. 1956. Osteology of the reptiles. Chicago: University of Chicago Press.

Romer, A. S. 1966. Vertebrate paleontology. 3rd ed. Chicago: University of Chicago Press.

Watson, D. M. S. 1957. On Millerosaurus and the early evolution of the sauropsid reptiles.
—Phil. Trans. R. Soc. Lond. (B) 240: 325-400.

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 (33.51S, 25.39E), collected by A. Smith, 15 January 1973.

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

7. SPECIAL HOUSE RULES

Capital initial letters

(a) The Figures, Maps and Tables of the paper when referred to in the text _
e.g. ‘... the Figure depicting C. namacolus ...’; ‘. . .in C. namacolus(Fig. 10) .. .’

(b) The prefixes of prefixed surnames in all languages, when used in the text, if not preceded
by initials or full names
e.g. Du Toit but A.L.du Toit; Von Huene but F. von Huene

(c) Scientific names, but not their vernacular derivatives
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.’ “et

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. f

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 Bio-
logical Abstracts.

SMITHSONIAN INSTITUTION LIBRARI
SUT
3 9088 01206 6478

ROBERT L. CARROLL
GALESPH YRUS CAPENSIS,

A YOUNGINID EOSUCHIAN FROM
THE CISTECEPHALUS ZONE OF SOUTH AFRICA