174 Mr. C. T. Regan on the Osteology and 



Division 1. Scoep^niformes. 



In all the members of this group the cranial osteology is 

 essentially similar; the opisthotic extends forward to the 

 prootie, which intervenes between parasphenoid and ali- 

 sphenoids ; a basisphenoid is present and the roof of the 

 ni^-odome is ossified. The hyo-palatine and opercular bones 

 are all present and normally developed. The post-temporal 

 may have the upper fork expanded and very firmly united to 

 tlie skull (some Scorpana, Apistus, Triglidse, Synanciidte). 

 Tiie radials are usu.:dly anvil-sliaped, but by reduction of the 

 iuterradial foramina may become plate-like (Triglidge, Choris- 

 viodactyluSj Trachicephalus^ Patcecus) ; sometimes the hyper- 

 coracoid and hypocoracoid may be separated by cartihige 

 (e. q. Triglidee, Inimicus, Synancia, Trachicephalus) . The 

 parapopliyses may be divergent and only the last ones bridged 

 across (many Scorpa3nidse, Triglidge) or may all be down- 

 wardly directed and completely united {Scorpcena, Aplo- 

 actidfe, Synanciidae). 



Family 1. Scorpaenidae. 



The skeleton of Sehastolohus aJascanus has been described 

 and figured by Starks (Proc. Calif. Acad. Sci. (3) i. 1898, 

 p. 361); other Scorpsenidse differ from it chiefly in un- 

 important details of the skull, the size of the second sub- 

 orbital, the form of the post-temporal, which may have the 

 upper fork much expanded and be very firmly attached 

 (Apistus and some species of Scorp>cena) , tlie degree of union 

 of the first radial and the hypercoracoid, which are usually 

 ankylosed, the number of vertebrse, and the direction of the 

 parapopliyses. Tlie vertebrae vary in number from 21 

 {Scorpcena^ Pterois)io?>i [Sehastes) ; Apistus \\?^%2& (11-1-15), 

 Tetraroge 26 (12 + 14), Centropogon 27 (11 + 16), and 

 Gymnapistus 28 (11 + 17). In the three last-named ribs are 

 present only on the prsecaudal vertebrse "with paropophyses. 



The Scorpajnidae are represented in the Lower Eocene 

 (London Clay) by the extinct genus Ampheristus ; other 

 genera have been described from the Upper Eocene and 

 Miocene. 



Family 2. Triglidae. 



The Triglidse are essentially similar to the Scorp£enida3 in 

 osteology, except that the hypercoracoid and hypocoracoid 

 are separated by cartilage, the pectoral radials are pUite-like 



