262 



TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



(a) that, at least in Sphyrana ideastes, a long ligament runs from the pelvis to the cleithral 

 symphysis (as I noted in dissecting a fresh specimen); {b) that in the relatively primitive 

 family of Atherinidae the pelvic bones are connected with the clavicular symphysis by a 

 ligament (Boulenger, 1910, p. 639), as in all the acanthopterygian fishes. 



Each of the existing families is plainly specialized in certain ways. The mullets 

 (Mugilidae) have a complex arrangement of the pharyngeal bones, a gizzard-like stomach 



C. fuscus 



Fig. 136. Cheilodactylus. After Leighton Kesteven. 



and an almost pig-like rim on the protrusile muzzle. The broad rounded skull (Fig. 138) 

 has a vertical concavity in the front wall of the mesethmoid which serves for the reception 

 of the expanded proximal end of the protrusile premaxillae and limits their posterior move- 

 ment. The stout parethmoids and paired anterior horns of the vomer support the massive 

 snout and protect the olfactory capsules. The lower edge of the lacrymal is denticulate 

 and overhangs the slender maxillae. The latter have long medial processes which meet in 

 the mid-line beneath the broad ascending processes of the premaxillae.. The teeth are 

 minute or villiform on the premaxillae and dentary. The lower or outer end of the rim-like 



