DESCRIPTION OF A NEW SPECIES OF ETHEOSTOMA (E. MICROP- 

 TERUS) FROM CHIHUAHUA, MEXICO. 



Charles H. Gilbert, 



Professor of Zoology, Indiana University. 

 Etheostoma micropterus sp. iiov. (No. 38245 U. S. Nat. Mus.) 



Color ill spirits : Light olive, sides and above obscurely tessellated 

 with darker. Xine short dark cross-bars on back, and traces of about an 

 equal number on middle of sides, those on front of sides faint, only the 

 last five evident. A black humeral spot present. A faint dark streak 

 downwards and one forwards from eye, and a small dark spot above 

 and behind orbit. Cheeks dusky ; top of head vermiculated with dusky 

 brownish. Spinous dorsal with a basal series of small blackish spots, 

 each in the midst of a translucent area, the terminal portion of mem- 

 brane rendered dusky by minute close set dark points. Soft dorsal and 

 caudal barred with light and dark lines. Pectorals and ventrals trans- 

 lucent, unmarked. The spinous dorsal probably showed bright colors 

 in life. 



Head 3§ in length ; depth 3f. Length of caudal peduncle nearly 

 equaling head. Least depth caudal i)eduncle equals one-half head. 

 D X, 1, 11 ; A II, 7. Lat, 1. 45^ (pores 31). 



Body extremely short and deep, the head short and heavy, moderately 

 compressed. Upper profile ot head rounded, no angle above orbits, 

 the short snout with rounded profile but not obtuse. Premaxillaries on 

 level of pupil, non protractile. Preorbital extremely narrow, little wider 

 than the broad end of the maxillary bone, which is not concealed by it. 

 Gill-membranes rather narrowly united across the isthmus, their width 

 anteroposteriorly one-half diameter of eye. Opercular spine bifid, with 

 two minute free i)oints. Preopercle entire. Eye large, 4 in head to 

 end of opercular spine. Interorbital space wide, strongly convex, its 

 width equaling length of snout, 5J in head. 



Fins all small. Distance from front of dorsal to tip of snout one-third 

 length. Dorsals low, the two joined at base, the last spine appearing 

 longer than the preceding one, and belonging to the second dorsal. 

 Longest dorsal spine one-third head. Length of last dorsal spine two- 

 thirds diameter of orbit, the spine erect and connected for its entire 

 height with the following soft ray. The next to the last spine is directed 



Prooeediu^is ^'ational Museum, VoL XIII.— Xo. 823. 



289 

 Proc. N. xM. 00 19 



