PLEOTOSPONDYLI CYPRINIDAE MEDA FULGIDA. 641 



or five and three-fourths exclusive of the caudal fin. The latter measure- 

 ment is four times the length of the head. The origin of the dorsal is 

 entirely behind the proper basis of the ventral ; its first spine is curved and 

 longer than the second, and its basis is intermediate between the base of the 

 caudal and the end of the muzzle. The dorsal rays behind the spine have 

 the basal two-thirds to one-half thickened and completely ossified; the artic- 

 ulated portions issuing from the apices of the spines. Radial formula : D. 

 II. 7; C. 19; A. I. 10-9; V. 2. V; P. 16. The first or osseous ray of 

 the anal is rudimental ; the fifth spinous ray of the ventral is bound by 

 nearly its entire length to the abdomen by a membrane. The pectoral rays 

 from the second to the sixth exhibit a basal osseous spinous portion, which 

 is not nearly so marked as in the ventrals. The pectorals reach the basis 

 of the latter. 



The lateral line is complete, and is slightly deflexed opposite the dorsal 

 fin. The lips are thin, and the end of the maxillary bone extends to the 

 line of the front of the orbit. Total length, (T.071 ; length to middle -of 

 basis of caudal fin, O m .05G5 ; to anterior basis of anal fin, O m .040 ; to basis 

 ventral, O n '.021 ; of head, O m .0145 ; of muzzle, (T.004 ; width at posterior 

 nares, O m .006 ; at middle of pterotic, O m .007S. Color, pure silver for a 

 considerable width above the lateral line. Dorsal region somewhat dusky 

 from minute chromatophorse. 



The plate affords a view of this species in profile and of the ventral 

 aspect. 



Numerous specimens from the San Luis Valley, Western Colorado. 



MEDA, Gir. 



Meda, GIR., Proc. Acad. Kit. Sci. Pliila., 185G, 192. Id., U. S. & Hex. Bound. Surv., 

 Ichthyology, 50. 



Tin's genus resembles Plagopterus in the absence of scales, while it dif- 

 fers in the absence of barbels and the reduction of the number of teeth of 

 the larger pharyngeal series to 4-4. Girard also asseiis twice that the 

 dorsal spine is "articulated", a character not observed by us in any species 

 of the group. His figure of M. fulgida represents the ventral radii as 

 articulated; but as there are other points in which it diifers from the 



description, it is probably inaccurate. 

 41 z 



