54 ANGLING. 



attaches to the inter-operculum) ; lastly, two small 

 pieces, 39 & 40, placed one above the other at the 

 anterior extremity of the branch, and serving to 

 unite it with the corresponding portion of the other 

 side. Anterior to this junction is the lingual 

 bone, 41, and behind it, in the angle formed by 

 the meeting of the two branches, and beneath the 

 branchiae, is a single piece, 42, usually vertical, 

 which uniting with the symphyses of the numerals, 

 forms what is called the isthmus, separating the 

 two branchial openings from below. 



VERTEBRAE, ETC. OF PERCH. 



The bones of the body, or trunk, consist of the 

 vertebrae of the back and tail, 67, 68, 69, for we 

 can scarcely say that there is any neck, and the 

 sacrum is wanting ; of ribs, 72, and the styles 

 which frequently adhere to them, 73 ; of the inter- 

 spinal bones, 74, which give support to the dorsal 

 and anal fins, 75, and 75 a ; and of the rays of those 

 fins, 75, 75 a , and of the caudal, 78, 71. These 



