Jordan and Evermann. Fishes of North America. 3159 



Known only from the Rio Verde, near Aguas Calieutes, Mexico. (Typo 

 No. 6154, L. S. Jr. Univ. Mus. Coll. J. O. Suyder.) 



Eslopsarum arge, JORDAN & SNYDER, Bull. TL S. Fish Com. 1899 (1900), 133, Rio Verde 

 near Aguas Calientes, Mexico. 



1 157 (b). CHIROSTOMA CHAPAUE, Jordan &. Siiyd r. 



Head 4; depth 5i; depth of caudal peduncle 3 in head; eye 3J; snout 

 3i; Intel-orbital space 4; height of spinous dorsal 3; soft dorsal If; anal 

 If; length of pectoral 1; ventrals 2+; caudal &; D. IV-10; A. 20; 

 pectoral 14; scales 47-13, 6 between dorsals. Body slender, compressed, 

 its deepest part below first dorsal; eye large, nearer tip of snout than 

 to posterior edge of opercle by a distance equal to 1 times the diam- 

 eter of pupil; interorbital space convex, its width about equal to diam- 

 eter of pupil or to preorbital area; syiuphysis of lower jaw project- 

 ing a little beyond tip of upper, the lips meeting; mouth oblique, lips 

 thickened posteriorly, the lower folding over the upper at their union ; 

 angle of mouth on a level with center of pupil; maxillary nearly vertical? 

 its distal end in advance of a vertical from anterior edge of orbit, a dis- 

 tance equal to | the diameter of pupil. Teeth minute, in bauds, not 

 arranged in definite rows; no teeth on vomer or palatines; gill-rakers on 

 first arch 30, very slender, the length of longest equal to diameter of 

 orbit; peritoneum black; air-bladder very large, extending posteriorly to 

 a point above middle of anal fin; vertebra? 45. A well-defined lateral 

 line extending along the body on the eighth row of scales below the first 

 dorsal. Scales large, crenate, not notably reduced in size nor closely 

 crowded together on any part of the body; those ou post-occipital region 

 and anterior to pectorals small; scales extending on basal f of inter-radhil 

 membranes of caudal; lower jaw, snout, and preorbital space naked; first 

 2 spines of dorsal highest, the following 2 a little shorter; first ray of 

 second dorsal highest, others gradually shorter; anal inserted a little 

 anterior to a perpendicular passing halfway between the origins of 

 dorsals, first ray longest, others successively shorter; when the fin is 

 elevated, its edge is concave; caudal deeply forked, the tips pointed; 

 pectoral notably pointed, extending past base of ventral a distance equal 

 to diameter of orbit; ventrals extending to vent. Color in life, translu- 

 cent; a silvery lateral band 1 scale wide, bright, and distinct posteriorly, 

 becoming indistinct anteriorly; upper edge of lateral band with dusky; 

 scales on dorsal part of body edged with dark dots; upper and lower 

 jaws with dark dots; upper part of eye black, the dark, pigmentecl 

 arachnoid showing through the thin skull. (Jordan & Snyder.) 



C. chapalw is closely related to C. grandocule, Steindachner. It differs in 

 having a smaller eye and larger scales. The former has 44 to 51 scales in 

 the lateral series, and 12 to 14 in a transverse series, while C. grandoctdc 

 has 60 to 62 scales in the lateral series and 15 or 16 in a transverse series. 



Known only from Laguna de Chapala, near Ocotlan, Jalisco, Mexico. 

 (Type, No. 6165, L. S. Jr. Univ. Mus. Coll. J. O. Snyder.) 



Chirostoma ehapalce, JORDAN & SNYDER, Bull. U. S. Fish Coin. 1899 (1900), 135, Laguna 

 de Chapala, Mexico. 



