PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 511 



Thirty-six individuals were captured at Artesia and four at Macon. 



Length from 2 to 2| inches. 



This species must be closely allied to Lythrurus atripes, Jordan, found 

 by Prof. S. A. Forbes in Southern Illinois. The differences are, how- 

 ever, sufficiently evident. The larger eye, shorter head, fewer scales 

 along the lateral line, and the fewer soft rays in the dorsal fin will dis- 

 tinguish my species from that. The peculiar coloration of the fins and 

 the lack of the dorsal spot will furnish the most obvious differences. 



This species illustrates well the little value of the character most 

 relied on for separating the Lytliruri as a genus from the species of 

 Minnilus. While the external characters are all, or nearly all, those of a 

 typical Lythrurus^ the teeth are decidedly "sharp -edged", as that term 

 must be defined in order to be applicable to other species with "sharp- 

 edged" teeth. 



Under the suhgenus Lythrurus I would arrange the following species. 

 There may be others that ought to be included : 

 Minnilus diplcemius (Eaf ) Hay. — Cope, Proc. Acad. Kat. Sci. Phila. 1867, 



162. Pennsylvania to Illinois. 

 M. cyanoeephalus (Copeland) Hay. — Jordan, Proc. Acad. Nat. Sci. Phila. 



1877, 70. Michigan to Minnesota. 

 M. atripes (Jord.) Hay.— Jordan, Bull. 111. Lab. :N'at. Hist. No. 2, 59. 



Southern Illinois. 

 M. ruhripinnis. Hay. — Mississippi. 

 31. ardens (Cope) Hay.— Cope, Proc. Acad. Nat. Sci. Phila. 1867, 163. 



Virginia and North Carolina to Kentucky. 

 31. helliis, Hay. — Mississii)pi. 



31. linis, Jordan. — Jordan, Annals N. Y. Lye. Nat. Hist. 1877, 342. 

 M. punctulatus, Hay. — Mississippi. 



As an aid to the identification of the species given above, I insert the 

 following analytical table : 



I. Elongated species ; depth in length 4^ or more times. 



1. Color pale, with a lateral metallic blue band M. lirus. 



2. Colors conspicuous — steel-blue, red, and purplish. 



a. A black spot at the base of the dorsal ; first ray of dorsal opposite the ventrals; 



A. I, 11 M. AUDENS. 



h. A black spot at the tips of the anterior dorsal rays ; first dorsal ray behind 

 the ventrals; A. I, 12 M. kubkipinnis. 



II. Deep and compi-essed species ; depth 4^^ times or less in the length. 



1. Species with a distiuct black spot at the base of doi-sal. 



a. Species with conspicuous hues; the dorsal surface dusky ; sides and fins with 

 more or less crimson. 



* Eye small, 4 in head; depth 3^ in length; D. I, 7 ; A. I, 11 M. atripes. 



** Eye in head 3^; depth in length 3|; D. I, 9; A. I, 11 M. dipl.emus. 



*** Eye in head 'Si; depth in length 4 ; D. I, H ; A. 1, 11 or 12. M. cyanocephalus. 

 h. Color pale; scales coarsely punctulated, small, 10 to 12—18 to .50-3; spot small. 



M. PUNCTCLATCS. 



2. No distiuct spot at the base of the dorsal; fins tipped with black M. bellus. 



