4 
Annals of the Transvaal Museum 
There are broad, shallow grooves, starting at the umbilical edge and com- 
pletely disappearing before reaching the middle of the flanks. Six of these 
grooves are present on the last whorl. They probabl}’- indicate old mouth- 
edges, for it seems as if each corresponds with a slightly broader interspace 
between the ribs on the outer portion of the flanks and the external surface. 
The direction of the broad grooves is the same as that of the ribs. 
The lobe-line is phylloid. This is not very clear in the text-figure, because 
the rounded terminations of the lobe-line are very delicate and easily suffer 
when the shell is treated with acid. They are, however, well visible in other 
lobe-lines shown in fig. i, PI. II. The lobe-line is of the greatly complicated 
type of the younger forms of the genus Phylloceras. On a radius of 9 mm. 
there are nine saddles, this number being also 
present on a radius of 25 mm. Most of the 
lobes are irregularly trifid, and the first lateral 
lobe has a large posterior development. The 
external lobe is short and this, together with 
the great size of the external branch of the 
first lateral lobe, gives the external saddle the 
appearance of overhanging the first lateral 
lobe. The first lateral saddle is the largest. 
The saddles diminish regularly in height from 
here to the umbilicus, in such a way, that a 
line touching their anterior ends is practically 
straight. This is also the case with a line touching the posterior ends of the 
auxiliary lobes. The whole of the auxiliary portion runs very slightly back- 
wards. The second lateral lobe is somewhat longer than the first auxiliary 
lobe. The external saddle, both lateral saddles and two auxiliary saddles are 
symmetrically divided by secondary lobes. On the last whorl of the largest 
specimen the second lateral saddle and first auxiliary saddle show a tendency 
of becoming trifid. 
Measurements : 
Text-fig. I. Phyllocerab Woodsi. 
Lobe-line of type up to the 
umbilical edge on a radius of 
9 mm. Nearly X4J. 
Type Paratype Paratype 
Diameter ... 
24-5 mm. 
(i-oo) 
46 
mm. (i-oo) 
20-3 mm. 
(I-oo) 
Height of last whorl 
14-6 ,, 
(o-6o) 
28 
„ (o-6i) 
II -7 
(0*58) 
Thickness of last whorl . . . 
7-4 ,, 
(0-30) 
13-2 
(0-29) 
6-4 „ 
( 0 * 32 ) 
Height of penult, whorl . . . 
4-9 „ 
(0-20) 
9*7 
„ (0-21) 
3-7 
(o-i8) 
Thickness of penult, whorl 
3-3 » 
( 0 - 13 ) 
4.8 
„ (o-io) 
2-9 „ 
(0-14) 
Diameter of umbilicus . . . 
2 ,, 
(o-o8) 
2-8 
„ (o-o6) 
1-8 „ 
(0-09) 
The type has suffered slightly and the large specimen somewhat more from 
crushing. 
Of the Indian forms Phylloceras Nera stands very near to the South African 
type. The general appearance of the two forms is strikingly similar. There is, 
however, a slight difference in the shape of the whorl and in the shape of the 
ribs. The grooves of the old mouth-edges are also different. The differences of 
the lobe-line are, however, striking. In Phylloceras Nera the auxiliary portion 
of the lobe-line runs more and more backwards, that is to say, both, the line 
touching the anterior ends of the saddles and the one touching the posterior 
ends of the lobes, are convex forwards, whereas in our form the first line is 
straight up to the first lateral saddle and the second up to the second lateral 
lobe. The lobe-line, text-fig. i, has been taken on practically the same radius 
as that given by Kossmat of Phylloceras Nera (12, PI. II, fig. 2, d). In P. Nera, 
however, the distance of the axis of the first lateral lobe, taken from a point 
between the tips of the two large secondary saddles, to the umbilicus, is i’84 
