324 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



Head naked, the surface sometimes crossed by papillary ridges. Body, 

 with small cycloid scales, irregularly placed." No lateral line. Vent 

 jugular, close behind the gill-openings. Ventral fins small or wanting ; 

 pectorals moderate, inserted higher than in most soft-rayed fishes; dor- 

 sal without spine, nearly opposite the anal ; caudal truncate or rounded. 

 Cranium without median crest. Stomach ccecal, with one or two pyloric 

 appendages. Air-bladder present. Ovary single. Some (and probably 

 all) of the species are ovo viviparous. In two of the genera the eyes are 

 very rudimentary and hidden under the skin, and the body is translu- 

 cent and colorless. Fishes of small size, living in subterranean streams 

 and ditches of the Central and Southern United States. Three genera 

 and four species are " all of the family yet known, but that others will be 

 discovered, and the range of the present known species extended, is very 

 probable. The ditches and small streams of the lowlands of our south- 

 ern coast will undoubtedly be found to be the home of numerous indi- 

 viduals, and perhai^s of new species and genera, while the subterranean 

 streams of the central portion of our country most likely contain other 

 species." {Putnam.) 



{Hcteropygu Guutlior, vii, 1, 2.) 

 a. Eyes rudiaieutary, concealed ; body colorless. 



1). Ventral tins present Amblyopsis, 153. 



J)h. Ventral tins obsolete Typhlichtiiys, 154. 



aa. Eyes developed ; body colored ; veutrals obsolete Chologaster, 155. 



153.— A1TIBI.YOPSIS DeKay. 

 (DeKay, New York Fauna, Fish. 1842, 187: type Amhhjopsis spelceus DeKay.) 



Eyes rudimentary, concealed under the skin. Surface of head crossed 

 by vertical tactile ridges. Gill-membranes fully joined to isthmus. Ven- 

 tral fins i^resent, quite small, close to anal. Colorless fishes of small 

 size, iuhabiting the cave-streams in the limestone regions of the West- 

 ern States. (a/jr^SAy?, obtuse; o^'':'?, vision.) 



520. A, spoSseus DeKay. 



Colorless. Mouth comparatively large, the length of its cleft about 

 equal to base of dorsal. Pectorals reaching front of dorsal; caudal 

 long, rather pointed. One pyloric ccecum. Head 3 in length ; depth 

 4.J. D. 0; A. 8; V. 4; P. 11. L. 5 inches. Subterranean streams of 

 Kentucky and Indiana. 



(DeKay, New York Fauna, Fish. 187; Giintlier, vii, 2; Putnam, Amer. Nat. 1872, 

 30, fig.) 



154.— Tl'PIIJLICHTIIYS Girard. 



(Girard, Proc. Acad. Nat. Sci. Pliila. 1859, G2: type Typhlichtiiys suhterranens Grd.) 



This genus differs from Amhlyo-psis only in the absence of the ventral 



