ACANTHOPTERYGII 



693 



serious objection could be raised to their union in one great 

 family with a number of minor divisions. 



The character from which the Scleroparei derive their name 



pile-. 



,pr 



FIG. 42,3. Left pectoral arch of A, Sebastes percoides; B, Scorpaenichthys mdi-mnmtvs : 

 C, Lactylopterus volitans. cl, Clavicle ; cor, coracoid ; pel, post-clavicle ; p.r, pec- 

 toral rays ; j>tr, pterygials ; ptte, post-temporal ; sc, scapula ; scl, supraclavicle. 



is subject to many modifications. The second suborbital (the 

 third if the praeorbital be regarded as the first) may be merely 

 enlarged and prolonged over the cheek towards the praeoper- 

 culum (Sebastes, Anoplopoma), or firmly ankylosed to the latter 

 (Scorpaena, Platyceplialus), or form part of the external armature 

 of the head (Trigla, Dactylopterus). The structure of the base of 

 the pectoral fin appears to afford important characters for the 

 definition of the families, as first pointed out by Gill ; these 



