CLUPEIN.E. THE GENERA AND SUB-GENERA. 2?5 



when 10,000 hogsheads have been taken on shore in 

 one port in a single day ; thus providing the enormous 

 multitude of 25,000,000 of living creatures drawn at 

 once from the ocean for human subsistence." 



(239.) We shall now enter into the detail of this 

 interesting group, — interesting from the importance 

 it possesses in an economic point of view, and doubly 

 so to the ichthyologist, because it is one of the most 

 perfect circular groups which we shall have to lay 

 before our readers. On this account, and from the 

 analysis we have been enabled to make of the whole, 

 we shall not merely enumerate the sub-genera, but 

 trace, in the principal or typical group, the series of 

 those links by which these latter types are united. 

 The primary divisions already enumerated, we consider 

 as genera ; the lesser ones, consequently, we view, with 

 Cuvier, as sub-genera. We commence with Clupea, 

 under which we place all those herrings that have the 

 teeth either minute or altogether wanting ; the body is 

 also much compressed, the belly sharp or serrated, 

 and the dorsal fin placed in the middle of the back. 

 By these characters we distinguish the true herrings from 

 the salmon-herrings, — a name we apply to those whose 

 teeth are very conspicuous ; for although the aberrant 

 forms of Megalops have the body or belly serrated, as 

 in all of the sub-genera of Clupea, yet the former have 

 well-defined teeth, which are not perceptible in the latter, 

 except, indeed, in Thryssa,oic that sub-genus which con- 

 nects the two groups. The position, also, of the dorsal 

 and anal fins, hitherto so little regarded that no notice 

 whatsoever has been taken of them, separates Clupea 

 from Chirocentrus, &c. ; so that the group becomes 

 very definite. 



(240.) Commencing with the herrings of Britain, 

 as the true type of the genus, we observe the dorsal 

 fin lunated, and placed nearly in the middle of the 

 back ; while the ventral fin (little inferior to the pec- 

 toral) is directly under it : the anal, in comparison to 



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