366 



TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



This broadly U-shaped fossa in Uranoscopus and Kathetostoma accommodates the 

 broadly oval articulating processes and the long but delicate ascending processes of the 

 premaxillae. The unusual width across the vomer, which lies immediately beneath these 

 broad articular processes of the premaxillae, is apparently conditioned not so much by the 



A TrachiriLLS 



Kathetostoma 



Fig. 245. Trachinus and Kathetostoma. Top views. 



breadth of the latter as by the general breadth of the mouth cavity, of which the vomer 

 forms the roof. Also the lower part of the hyo-branchial complex is unusually broad and 

 this broad part occludes against the widened vomer. Finally the opposite lacrymals and 

 prefrontals spread wide transversely, further broadening the roof of the mouth. The 

 mesethmoid is small, partly because it is squeezed down between the ascending and 



pn« mx 



U.bicinctus Uranoscopus sp 



Fig. 246. Uranoscopus. 



