356 
A. M. REESE 
the horizontal part of the canal, especially towards its anterior 
end, is a row of smaller openings. According to Garman ('88) the 
angular extends only to the point where the nasal is given off, 
anterior to which point it is known as the subrostral. As there is 
no change whatever in the character or direction of the angular 
at this point there seems to be no reason for changing its name, 
so that it will here be called the angular from the point of union 
with the orbital to the point of union with the median subrostral, 
on the antero-ventral side of the snout. In one of the two speci- 
mens of C. monstrosa studied by Garman the angular arose from 
Fig. 4. An anterior view of the head of C. colliei, showing the distribution of 
the canals. 
the jugular, just after the latter came off from the orbital; in none 
of the numerous specimens of C. colliei studied by the writer was 
this the case. Hubrecht (76) figures the angular as arising from 
the orbital as in the present form. The exact course of the angular 
canal in Rhinochimsera and Harriotta could not be determined 
from Garman's description, nor from his figures or those of Dean, 
but it is, apparently, very similar to the condition here described. 
In Callorhynchus, according to Garman's description, ^^Not far 
in front of the oral the angular descends tow^ards the mouth from 
the suborbital. As it nears the lip it takes more of a forward 
course, and, following near the border of the rostral flap, finds 
its way down and backward to the edge of the lower surface, where 
