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TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



A "subtemporal bone," lying above the opercular, is recorded by Ridewood in the 

 salmon as well as in Chanos. Perhaps this bone, which is of unknown origin, is indicated in 

 the Cretaceous elopid genus Osmeroides (Woodward, A. S., 1901, PI. II, Fig. 1). The 

 origin of the "subtemporal bone" is discussed below (p. 166). The maxilla is thin and 

 elongate, recalling that of the Cretaceous Thrissopater. 



pfs>pareth 



Salmo 



Fig. 48. Salmo sp. (A) and Chanos salmoneus (B). Comparison of skull tops. 



The salmon family (in the broad sense) dates only from the Miocene epoch but 

 Agassiz and subsequent authorities have recognized its relationship with the Clupeidse. 



Starks notes (1926a, p. 150) that in Argyrosomus hoyi, representing the Coregonidae, 

 which are generally admitted to be closely allied with the Salmonidse, the ethmoid region 

 in general resembles that of the fishes of the family Clupeidae. 



Frost (1925a, p. 157) notes that the Salmonoidea agree with the Clupeoidea in the 

 prominent development of the saccular otolith (sagitta) and show in their otoliths their 

 relationship to the Elopidae. 



In his recent article on the phyletic classification of the teleosts. Professor Garstang 

 (1932, pp. 253, 257, 258) removes the Salmonidae very widely from the Clupeidae, assigning 

 them to his first grand division (Haplophysi) of the Teleostei, while the Clupeidae are 



