58 AMERICAN ANGLER'S BOOK. 



The reader will observe the peculiar shape of the second 

 dorsal of the first figure ; it is one of the characteristic markwS 

 of the Salmonidse. No other family the angler meets with, 

 has it except the Siluridse (Catfish). This fin is adipose, 

 generally opaque, and without rays — being nothing more 

 than a flexible cartilage. 



The first figure of the annexed wood-cut represents a front 

 view of the open mouth of one of the species of the Salmon 

 family, and shows the position of the teeth. Those along the 

 centre of the roof of the mouth above 1, are on the vomer ; 

 those on the sides above 2, are on the palate ; those around 3 

 are the pharyngeal teeth ; those on the edge of the upper jaw, 

 are the upper or super maxillaries ; and, those on the edge 

 of the lower jaw, the lower or inferior maxillaries. 



"^^^^ 



The second figure of the same plate shows the anatomical 

 structure of the head, including a side view of the teeth. 

 1 is the preopercle or fore gill-cover ; 2, the opercle or gill- 

 cover proper ; 3, the subopercle or under gill-cover ; 4, the 

 interopercle or intermediate gill-cover ; and 5, the branchios- 

 t^gous rays, or, as they are more generally termed, the 

 branchial rays.. 



By reference to the foregoing wood-cuts, and reading with 

 some care, scientific descriptions of fish, an angler may be 

 able to describe any species, which may be unknown to him, 



