126 
FOSSIL LEPTILIA OF THE 
a score more for the wanting pinnigerons terminal portion of the tail, which probably 
has been torn off by predatory assailants of the dead reptile. 
Besides the Liassic locality of Barrow-on-Soar, specimens and parts of Ichthyosaurus 
lonyirosiris occur in the zone characterised by JEgoceras anyulatum ; also in the zone of 
Arietifes BucUandi} 
1 . Ichthyosaurus latimanus,® Ow. PI. XXXIII, figs. 2, 7. 
This species is nearly allied to Ich. communis in the size and construction of the 
pectoral paddle ; but the still smaller proportion of the pelvic one suggested the nomen 
triviale, which is vindicated, also, as a sign of specific difference, by the proportionally 
shorter and thicker jaws and by the modification of the vertebral centrums (PI. XXXIII, 
figs. 2 and 7) ; in this character the present species dififers from Ich. hreviceps. 
Ich. latimanus resembles Ich. communis in the ventricose, subobtiise character of the 
teeth, or, at least, some of the more worn ones, of the twenty-nine which may be counted 
on each side of both jaws. The articular surfaces of the centrum are concave at the 
middle third, the rest of the surface to the circumference is flat. 
In the specimen of Ich. latimanus, 6 feet 10 inches in length, and in that of an Ich. 
communis, 5 feet 2 inches in length, the following were the respective dimensions of 
bones of the scapular arch and its appendage : 
Ich. latimanus. Ich. communis. 
In. 
Lines. 
In. 
Lines. 
Scapula, length of . . 
3 
4 
3 
0 
Coracoid, antero-posterior diameter 
3 
8 ... 
2 
4 
Coracoid, transverse diameter 
3 
2 
2 
0 
Antibrachials, breadth of . 
2 
5 
I 
7 
Length of fore fin, humerus inclusive 
7 
6 
5 
0 
Breadth of ditto 
3 
6 
2 
4 
The clavicle is proportionally thicker than in Ich. communis ; in the skeleton above 
cited it is 6 inches 8 lines in length. 
The head is relatively shorter. In the specimen of wLich the dimensions are above 
given the mandible is 1 foot 4 inches in length, while in the Ichthyosaurus communis 
above compared it is 1 foot 5 inches in length. 
In a specimen of Ichthyosaurus latimanus in the Museum of the Philosophical Institu- 
^ See the classical Monograph, by Dr. Wright, F.R.S., &c., in the volumes of the Palaeontographical 
Soeiety issued in 1878 and 18/9. 
2 ‘Report,’ ut swpra p. 123. 
