194 ACANTHOPTERYGII. — FISTULARIAD^. 



lengthened, flattened sidewise, and coming to an 

 edge along the back. They have only two or 

 three gill-rays, which are slender. There are two 

 dorsals, the first strongly spinous, and both placed 

 far behind ; and small ventrals situated behind 

 the pectorals. The mouth is very small and opens 

 obliquely ; the intestinal canal has two or three 

 folds, but no csecal appendages ; there is an air- 

 bladder of considerable size. Ten species are 

 comprised in this sub-family, forming two genera ; 

 they are scattered over the Atlantic and Pacific 

 Oceans ; one is common in the Mediterranean, 

 whence it occasionally wanders to the southern 

 shores of Great Britain. 



Genus Centriscus, (Linn.) 



In this genus the form is short and compressed, 

 the depth much exceeding the transverse diameter 

 of the body ; the head is not far short of half 

 the whole length, much produced into a slender 

 tube ; the mouth, opening at the extremity, is 

 very small, and destitute of teeth. The first 

 dorsal is situated far back, and contains three or 

 four spinous rays, of which the first is large and 

 strong, connected by intermediate pieces with the 

 bones of the shoulder and the skull : being thus 

 supported, and very stout and strong in itself, 

 and armed with a series of rugged teeth along 

 its hinder edige, this spine forms a powerful 

 weapon of offence and defence, capable of being 

 moved at the will of the animal. The ventral 

 fins are small and united. The body is covered 

 with small scales, and with some larger toothed 

 ones over the bony apparatus that connects the 



