Suborder Salmonoidea 



COMPOSITE AUTHORSHIPi 



Characters and Key to Families 



HENRY B. BIGELOW 



Museum of Comparative Zoology 

 Harvard University 



Characters. Isospondylous fishes with Pelvic fins abdominal in position, and with 

 an Adipose fin between the rayed dorsal and caudal fin. 



Scales. Body and tail sectors of trunk with scales everywhere in most, but naked 

 in some Salangidae;^ head naked; scales thin, rounded. Luminescent organs (photo- 

 phores) absent. 



Maxillary bones as well as Premaxillaries taking part in formation of upper 

 jaw. Teeth of moderate size in most, but those on lower jaw in the form of canines in 

 a few, perforating the upper jaw; teeth present on premaxillaries, maxillaries, palatines, 

 vomer (except in some Salangidae), dentary portion of lower jaw, and tongue in most; 

 teeth small or absent among the Coregonidae. 



Pectoral girdle with a mesocoracoid element in most; lacking in the Salangidae. 

 Last few Vertebrae upturned in Salmonidae, Coregonidae, and Thymallidae; a single 

 vertebral centrum turned upward in the Osmeridae, but conditions in this respect seem 

 not to have been reported for the Salangidae. 



A Swim bladder in most, connected to the alimentary canal by a permanently 

 open duct; no swim bladder in Salangidae. Oviducts incomplete insofar as known, 



1. Characters and Key to Families by H. B. Bigelow; Family Salmonidae and Genus Salmo by J. R. Dymond; Genera 

 Sal-velinus and Crislivomer by H. B. Bigelow; Family Coregonidae by H. B. Bigelow; Family Osmeridae by 

 H. B. Bigelow and William C. Schroeder. 



2. The Salangidae are described {46: 239) as "naked, or with a few exceedingly thin, large, scattered deciduous scales." 

 For illustrations of the salangid dentition, see Fang (^6: 240, fig. i; 246, fig. 3; 252, fig. 8; 260, fig. 10). 



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