Dr. Baikie on the species o/* Crocodilus of Central Africa, 379 



forehead ; at the ninth tooth more than two-thirds the distance be- 

 tween the eye and nostrils. 



Measurements, 



No. 1. No. 2. No. 3. No. 4. 



in. in. in. in. 



Extreme length 26 24^ 22^ 21 



Greatest width behind 12f 12 11 1 lO-]- 



Distance from eye to nostril. . lOf 10 9 8f 



Breadth at ninth tooth 7f 6i 6^ 5f 



Breadth at notch 41- 3f 3| 2f 



Width of forehead, anteriorly. 5 4i 4^ 4 



Width of forehead, posteriorly 6^ 5f 5;|; 5 



Extreme length of lower jaw .. 29 27 24-|- — 



The proportions of all these correspond almost exactly, and I have 

 ascertained the proportional measurements of a smaller one to be the 

 same, although from its being in pieces and not yet put together, I 

 have not time to take the exact dimensions. They show the Croco- 

 dile from the Binue to be proportionally longer than C. vulgaris, and 

 much more so than C. marginatus, to be in form of upper surface 

 and of forehead near the latter, but without the prominent sides to 

 the forehead, — also in breadth at the ninth tooth to agree with C. 

 marginatus, while the converging shape of the forehead diifers from 

 both. 



I shall add some few other general characters derived from these 

 skulls : — Cranial fossse somewhat oblong and ear-shaped, converging 

 anteriorly, and almost touching by their inner and anterior margins, 

 the outer side being nearly straight. Orbits with a slight notch an- 

 teriorly. Nasal foramen broadly pyriform, and almost quadrilateral. 

 Foramina for the two anterior teeth converted in old specimens into 

 deep notches. Articulating extremities of lower jaw much curved 

 inwards. 



I have compared these skulls with twelve others of Indian and 

 American species, from all of which they are quite distinct. 



The ninth upper tooth of Crocodiles is said to be enlarged like a 

 canine, but this is not strictly correct. I have examined the denti- 

 tion in eighteen skulls of various species ; in the lower jaw there are 

 always nineteen teeth, but in the upper jaw the number in the adult 

 is seventeen on either side, while in the young it is eighteen. This 

 is owing to the second incisor being deciduous, and in old skulls the 

 socket is completely obliterated by the enlargement of the foramen 

 for the two anterior teeth. Thus in old animals there are only four 

 teeth in each intermaxillary bone, while in younger individuals there 

 are always five. So, more strictly, it is the tenth and not the ninth 

 upper tooth which is enlarged. 



The characters which I have above enumerated seem to me di- 

 stinctive, and possibly on further investigation, when the entire animal 

 is examined, and its external characteristics determined, it may prove 

 a new species. The Crocodiles which I saw on the mud banks, or 

 swimming about in the river, appeared of a d£U*k green colour. 



