ANALYSIS OF SPECIES OF MYXOSTOMA. 117 



•Lips distinctly plicate — Continued. 



cc. Scales very small for the genus, about 9-56-8 in number : body moderately 

 elongate, the dejith about 4 iu the length. 

 ee. Head shortish, conic, the snout not much projecting, about 4 in length : 

 eye large : dorsal tin .-^mall, with about eleven rays, the last rapidly 

 shortened (characters of moutli uukuowu, but probably similar to 

 viacrolepidotum ami jJoecUura ; it is said to be " much larger than in 



P. congestuti") aljjiuuji, 11. 



aa. Species with the body elongate, little compressed, broad, the dep^i about a 

 in length, not very much greater than the thickness. 

 j. Head very short, roundish above, rather pointed forwards, 

 about 5 in length : cheeks subvertical : mouth rather large, 

 with thick lips, which are strongly plicate, the folds some- 

 what broken up : eye small : tins very small, the dorsal 

 rays 10 to 12 : scales rather large, (5-44 to 49-5 : color green- 

 ish-brown, a pale blotch on each scale, these forming con- 

 tinuous streaks along the rows of scales : back with more 

 or less distinct brownish cross-blotches ; fins brownish, not 

 much red; the dorsal blackish at tip: size smallest: length 



less than a foot CERVINUM, 12. 



tt Lower lip thin, not infolded and "/V-shaped ", forming a narrow, crescent-shaped 

 border around the mandible. 

 k. Head small, 5 times in length : muzzle prominent, but 

 less so than in M. coregonus : month moderate : back a 

 little elevated: depth about 3^ in lengih: dorsal rays 12 

 to 14, its free border of^en incised : scales G-45-5 : colora- 

 tion very pale; lower fins white: size large; reaches a 



weight of four pounds or more album, 13. 



kh. Head stout, as in M. velatum, rather long, 4 in length, 

 flattish above, muzzle truncate, not very prominent : 

 mouth moderate : back elevated : dorsal tin long, of 14 

 or 15 rays : sea-green above ; white below ; lower fina 



white THALASSINUM, 14. 



ttt Lower lip, infolded, /V-shaped when viewed from below, with a distinct median 



crease, iu which the two halves of the lip meet, forming 



an acute angle : mouth small. 



I. Dorsal large, with 1(5 (15 to 17) developed rays. 



m. Body stout, deep, compressed, the back elevated, the 



depth 3 to 4 in length : head short, heavy, flattish 



and broad above, thick through the cheeks, 3f to 4J 



in length : eye rather large, midway in head, 4 to 



5 in its length : muzzle rather prominent, blnntish, 



overhanging the very small mouth : fins very large ; 



dorsal long and hi^h, its height five-sixths the length 



of the head : pectorals nearly reaching ventrals • 



color silvery, smoky above; lower fins red: size 



large velatum, 15. 



