898 THE AMERICAN NATURALIST. [VoL. XXXIX. 
which have their origin from a median line of aponeurosis and 
run obliquely forward and laterally to the cartilage of the lower 
jaw. This median aponeurosis starts at the level of the first 
gill slit, about half an inch in front of the pectoral girdle, and 

Fic. 4.— Ventral view of Acanthias showing the ventral longitudinal muscles. The right half 
a deeper dissection than the left. Cac, coraco-arcualis communis; CBr 7, coraco-branchi- 
: CHy hvoid 
alis ; ; Cm, coraco-mandibularis. 

extends to within half an inch of the symphysis of the lower jaw. 
The other ventral constrictors (Csv 2-6) are visible at either 
side of the coraco-arcuales communes. 
The first ventral constrictor (Fig. 5, Csv 7) arises from the 
