226 APODES. 



ORDER VIII. — M ALACOPTERYGII 

 APODES. 



In this order, we are presented with a family 

 distinguished by their long, serpent-like bodies ; 

 a thick, remarkably tough skin, and though it is 

 generally conceded that they have swimming- 

 bladders, they are either too small to be of much 

 service, or answer some other purpose in their 

 economy, as nearly all of them prefer concealment 

 on a muddy bottom, rather than clear water. 

 The spine usually contains one hundred and six- 

 teen vertebrae, so slightly attached that they are 

 exceedingly flexible. Lastly, most of the fishes 

 of the auguilliform structure are viviparous. Gen- 

 erally the head is smooth ; the eyes defended by 

 the skin, (conjunctiva,) as in serpents ; the body 

 nearly round and slippery, in consequence of a 

 slimy excretion ; in the gill membrane are com- 

 monly ten rays ; the branchial openings are near 

 the head, and usually close to the pectoral fins ; 

 the dorsal, caudal, and anal fms are united into one 

 like a border. The color seems to vary accord- 

 ing to the character of the water they inhabit. 



GEN. AI7GUILLA. 



The Common Eel, — Auguilla Vulgaris. 



