332 
SELACmi. 
The jaw shown in the accompanying woodcnt (fig. 13), is some- 
times termed upper *, and sometimes lower In his latest remarks 
upon the subject, Sir llichard Owen states that it represents the 
lower dentition, which differs from the upper in the presence of an 
uzygous series of syraphysial teeth. So far, however, as the present 
writer has had the opportunity of observing, this character is not 
constant. 
Jaw of Cestracio>i philipj/i. — Bocont. 
In the living species the ptcrygo-qnadrate cartilage articulates 
with the preorhital region of the cranium, but it is impossible to 
determine whether such was the case in the extinct species here 
referred to the same genus. 
Cestracion falcifer, Wagner. 
18-')2. Cegtraciem, F. A. Quenstodt, Ilandb. Potrefakt. p. 178. 
1867. Cestracion falcifer, A. Wagner, Gelehr. Auz. bay. Akad. Wiss. 
vol. xliv. p. 290. 
1803. Acrodus falcifer, A. Wagner, Abh. k. bay. Akad. Wiss., niath.- 
phys. Cl. vol. ix. p. 301, pi. v. fig. 1. 
‘ E. Owen, Paleontology, 2nd edit. (1801), p. 127, fig. 41. 
’ R. Owen, Gteol. Mag. vol. vi. (1869), p. 196. 
