SALMONID^. CV. 271 



variations due to age, sex and food are very great, and 

 have led to the establishment of a great number of nomi- 

 nal species in all the leading genera, particularly in 

 Salmo. 



* Jaws with evident teeth. 



f Dorsal moderate, of less than 20 rays; teeth strong, on jaws, 



voiner and tongue. 

 \ Scales small, often imbedded in the skin; lat. 1. 100 or 



more SALMO, 1. 



\\ Scales moderate, deciduous, not imbedded ; lat. 1. 60 to 70. 



OSMERUS, 2. 

 ft Dorsal very high of 20 or more rays ; teeth small. 



THYMALLUS, 3. 



**. Teeth wanting or reduced to slight roughnesses ; scales rather 

 large, loose . . COREGONUS, 4. 



/. SALMO, Linnaeus. SALMONS. 

 j^~ For Revision of this group see Addenda, page 355. 



* Anadromous species, running up from the sea into fresh water 



to spawn; the young remaining there for a time, then return- 

 ing to the sea where they remain except during the season 

 of reproduction; upper jaw in males moderately if at all 

 hooked. (Salmo.) 



1. S. salar, L. GREAT SEA SALMON. No red spots; 

 young (known as Parr, or Smolt) with dusky cross bars; 

 males in the spawning season with the lower jaw strongly 

 recurved and hooked; body covered with black and red 

 patches; others silvery, with small black dots; eleven or 

 twelve scales in a transverse series from behind the adi- 

 pose fin obliquely forward to the lateral line; D. 14; A. 

 11; lat. 1. 120. Northern Europe and America, S. to 

 Cape Cod. 



2. S. quinnat, Rich. COLUMBIA RIVER SALMON, known 



