194 



TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



the family, and the lower line of the sulcus is domed as in the Characiformes. Another 

 Characid feature is the position of the asteriscus in the cranial cavity. These points con- 

 firm Mr. Regan's contention that Barilius is the most primitive of living Cyprinoids. 



"The otoliths of other species of the Cyprinidae, while resembling the Characid type 

 in certain features, such as the radiating furrows of the outer side and the serrated edges, 

 mx 



pmx 



A 



HeTerobranchus 



Chrysichthys 



Fig. 77. Skull tops of two catfishes. 



A. Hrterobranchus longifitis. Family Clariidse. 



B. Chrysichlhys sp. Family Bagridse. 



are generally elongated and also differ in the shape of the sulcus, owing to the lower line 

 being either straight or distended ventrally instead of being domed. 



"In the Cobitidae and Homalopterids, the asteriscus, which throughout the remainder 

 of the suborder appears to be invariably the largest of the three otoliths, gives place in 

 importance to the lapillus, this feature occurring elsewhere onlv in the succeeding suborder, 

 the Siluroidea." 



