XXIII ACANTHOPTERYGII 703 
Berycidae ; and the resemblance which their terminal forms bear 
to the Anacanthini is, as pointed out by Regan, probably to be 
ascribed to convergence, not to any close genetic affinity, as 
hitherto believed by many authors. 
y SS cor 5 
pelv SS picl 
Fic. 427.—Pectoral arch and pelvis (left side) of A, Trachinus draco; B, Percophis 
brasilianus ; cl, clavicle ; cor, coracoid ; pelv, pelvis; pt, pterygials ; ptcl, post- 
clavicle ; pte, post-temporal ; sc, scapula; scl, supraclavicle. 
The character of the position of the scapular foramen, either 
in the scapular bone or between it and the coracoid, which 
obtains in many genera of this division as well as in most of the 
Anacanthini, has proved to be unreliable even for the purpose 
of family definition ; it is, however, of assistance in determining 
the relation of certain obscure, degraded forms placed by some 
authors with the Anacanthines, by others with the Blenniids. 
SYNOPSIS OF THE FAMILIES. 
I. Pectoral rays attached to the scapula and to a series of pterygials of 
which only one or two are in contact with the scapula (see Fig. 427); ventral 
fins jugular, with 1 spine and 4 or 5 soft rays; anterior dorsal rays usually 
spinous or not articulated, often forming a detached fin. 
A. Epipleurals present. 
1. Second suborbital produced inwards to support the eye-ball. 
Ventrals close together ; scales very small, cycloid, forming oblique bands 
1. Trachinidae. 
Ventrals widely separated . : . : . 2 Percophiidae. 
2. No subocular shelf. 
Ventrals widely separated ; two nostrils on each side 3. Leptoscopidae. 
Ventrals widely separated ; a single nostril on each side 
4. Notothentidae. 
Ventrals close together; scales very small, forming oblique bands; head 
partly covered with bony plates : : . 5, Uranoscopidae. 
