No. 2.] GRAMMICOLEPIS BRACHIUSCULUS. 285 
The cranium of the Cavanx No. 11,385, which bears a very 
close resemblance to C. hzppos, shown in Fig. 6, although, be it 
known, it possesses marked differences, is composed of a bone 
tissue much more like that seen in the cranium of Grammiico- 
/epis than any of the other specimens before me. As much as 
it is unlike it, it evidently approaches the semi-transparent and 
brittle condition found in our subject. The next thing that 
our attention is directed to, is the strikingly large orbit of this 
Caranx, and the evident, though distant, similarity of the ele- 
ments that go to form its walls. The chief difference we meet 
with here is the absence in the Cavanx of the backward-extend- 
ing plate of the ethmoid seen in Grammicolepis, while there is 
much to support a probable relationship of the forms, in the 
parasphenoid, the basisphenoid, and less so in the prefrontals, of 
the two. | 
Figure 6.— Left lateral view of cranium of Caranx hippos. Spec. No. 13,561, Col- 
lection of the Smithsonian Institution; life size, by the author. Letters signify the 
same as in the other figures. 
Again, in the Carvanx, the ethmoidal mass, and parts, which of 
a consequence associate with it, are produced forwards, and we 
fail to find anything upon this aspect that in any way reminds 
us of the curiously truncate appearance of the front part of the 
cranium in Grammtcolcpis. 
Another marked difference is seen in the vomerine element ; 
this bone, as we have observed, is in our subject merely a kite- 
shaped scale, in no way incorporated with the parasphenoid, 
being merely attached around its anterior rim. Now our speci- 
