NATURAL SCIENCES OF PHILADELPHIA. 267 



XIPHOSTOMA TMBO, Cope, sp. nov. 



D. 10, A. 10 ; sca,Jes of lateral line 15. Last dorsal ra}^ above 

 the fifth anal. Head (without membranous flap) three times in 

 length to basis of caudal ; eye 7.6 times in length of head, of 

 which four times enter muzzle (without flap) ; flap equal one 

 diameter of eye; interorbital space flat, 1.75 times diameter of 

 orbit. Muzzle flat above, decurved, receiving the mandibular 

 teeth within it, striate rugose. Teeth minute, equal. A rudi- 

 mental dermal flap on mandible. Pectoral fins reaching less than 

 .3 distance to ventrals ; rays 15 ; Y. 8 ; extending half-way to 

 anal. Caudal emarginate. Depth of body at ventrals 7.75 times 

 in length without caudal. 



Color light brown above, below white ; two series of small 

 brown spots on each side, above. Top of head rosy; dermal flap 

 of muzzle vermilion, black-edged. Opercula golden, suborbital 

 bone with purple reflections. Dorsal fin yellowish, with two brown 

 cross-bands ; anal with a median black spot. Caudal fin with 

 middle and tips black, margin and space between, with raj's, 

 white. 



Total length .203; to orbit .036; to ventral .112; to dorsal 

 .1382 ; to anal .1432 ; to caudal fin .178. 



Two specimens from the Ambyiacu. 



MYLETES ALBISCOPTIS, Cope, sp. nov. 



DiscoidaljWith small head ; anal rays long, the fin half covered 

 with scales. Radii D. 17 ; A. 36 ; Y. 7. Caudal fin subtruncate. 

 Scales small, 41-100-45. Forty-seven spines in front of the anal 

 fin. Profile scarcely concave, orbit 3.5 times in head, a little less 

 than half the superficial width of the very convex interorbital 

 space. Length of head 3.75 times in total, lacking caudal ; deptk 

 1.4 times in same. Anterior teeth separated from posterior. 

 Pectoral fin to ventral, ventral commencing under dorsal. First 

 ra}"- small, not reaching vent. Length .16 m. ; to line of dorsal 

 (axial) .065 ; to line of anal (axial) .09 ; to caudal .125. 



Color silvery, with blue reflections above, and golden below. A 

 black spot on posterior edge of operculum; otherwise immaculate. 



Numerous specimens from the Amb^'iacu. Two from the Per- 

 kins collection lack the opercular spot. 



1872.J 



