Jordan and Evermann. Fishes of North America. 2305 



855. MYXODAGNUS,* Gill. 



Myxodagnus, GILL, Proc. Ac. Nat. Sci. Phila. 1861, 269 (ojjercularis) . 



Tliis genns differs from Dactyloscopus in the form of the head, which is 

 elongate-conoid, the lower jaw obtusely pointed and provided with a 

 short flap in front. The pseudobrauchia 1 - are well developed and the 

 dorsal fin commences far behind the nape. One species known. (Myxodes, 

 a genus of blennies, which this fish resembles in form; Agnus, ayvo$, an 

 old name of Uranosoopus scabcr.) 



2643. MYXODAGXUN OPERCULARIS, Gill. 



Head 5 without lower jaw; depth 7. D. 36; A. II, 36; scales 2-44-9; 

 pectorals equal head; ventrals If; caudal 1J. The body is deepest at 

 front of dorsal fin, tapering regularly to the caudal fin. Head elongated, 

 acutely conical ; profile nearly straight, but slightly concave in front of 

 the eyes; the crown is transversely arched and smooth; the frontal bones 

 between the eyes are exceedingly narrow, so that the orbits appear sepa- 

 rated by little more than a mere septum; eyes large, longitudinally ellip- 

 tical; opercular pores obsolete; the postorbital or temporal ridge is nearly 

 as long as the diameter of the orbit; the opercular fringe is composed of 

 6 or 7 short filaments; origin of dorsal above vent, the fin very low and 

 continuous, its last rays not reaching to base of caudal rays; anal com- 

 mencing slightly in front of dorsal, similar to it but higher, its last ray 

 reaching to base of caudal rays ; pectoral large and pointed, reaching to 

 curve in lateral line ; rays of ventral subequal, reaching about to vent ; 

 caudal truncate; scales moderate, finely striated concentrically and 

 arranged in 11 rows on each side; the lateral line runs through 12 scales 

 on the sides of the back, is then deflected through 3, and thence runs 

 along the fifth row from the back through 36. Color light yellowish 

 brown, rendered darker on the back by congregations of dark spots on 

 the scales; there is a pearly patch behind and beneath the eye, and the 

 operculum is also colored in the same manner. (Gill.) Cape San Lucas. 

 Described from a specimen 24- inches in length. Not obtained by recent 

 collectors, (opercularis, pertaining to the gill cover.) 



Myxodagnus opercularis, GILL, Proc. Ac. Nat. Sci. Phila. 1861, 270, Cape San Lucas. (Coll. 

 Xantus.) 



Family CXCVII. URANOSCOPIDvE. 

 (THE STAR-GAZERS.) 



Head large, broad, partly covered with bony plates. Body elongate, 

 conic, subcoinpressed, widest and usually deepest at the occiput. Body 

 either naked or covered with very small, smooth, adherent scales, which 



* This genus is thus denned by Dr. Gill: Body quite slender, the greatest height con- 

 tained about 10 times in length. Head rather elongated and acutely conical, about twice 

 aalong as high; eyes large and elliptical, and very closely approximated ; frontal bones 

 extremely narrow. Mouth oblique; lower jaw projecting much beyond the upper and 

 furnished with a short, compressed, and wide flap or barbel in front of the symphysis ; 

 villiform teeth present only on the jaws. Dorsal fin inserted behind the vertical of the 

 anus, and furnished with simple and articulated rays; anal fin as long as or longer than 

 the dorsal. 



