Jordan and Evermann. — Fishes of North America. 1065 



covered with large, imbricated, very rough scales, these less closely set 

 below; breast naked; behind the ventrals the middle line of the belly 

 with some small scales, behind which is a naked space bounded l)y small 

 embedded scales, and extending as far as tLe vent; back, from middle of 

 first dorsal forward, naked, jjosteriorly more or less scaly. Fins low and 

 small, the second dorsal longer than the first or the anal, the spines 

 slender; anal spines short ; pectoral tins long and narrow. Translucent, 

 with small dark spots on back and sides, besides tiner specklings ; fins 

 plain. Length 2 inches. Southeastern Virginia and eastern North Caro- 

 lina ; locally abundant in clear sandy streams in pine woods, (riireus, 



Pwcilic}i(hys vilreus, Cope, Proc. Amer. Philos. Soc. Phila., 1870, 2G3, Walnut Creek, a tribu- 

 tary of Neuse River, Wake County, North Carolina. (Coll. Cope.) 



loa vitrea, JoRiiAN & Gilbert, .Synojisis, 490, 1883. 

 Ammocrijpla vUrea, Buulengek, Cat., i, 102. 



1453. lOA VIGIL, Hay. 



Head 3f ; depth 6; eye 3, greater than snout. D. X-12; A. II, 10; scales 

 about 60 in longitudinal series. Body slender ; head long ; caudal pedun- 

 cle compressed and comparatively deep, the fish, therefore, having nearly 

 the same depth throughout its length. Top of head sloping gradually 

 from occiput to snout. Upper jaw protractile ; mouth large, terminal, 

 slightly oblique; the jaws equal, maxillary reaching anterior edge of 

 pupil ; interorbital space very narrow ; jaws with recurved teeth ; oper- 

 cular spine well developed ; opercles and cheeks naked. Dorsal fins well 

 separated ; the origin of spinous dorsal i distance from snout to base of 

 caudal, its length ^ and its height ^ length of head; soft dorsal same 

 size as spinous. Length of aual fin f length of head, its height i head. 

 Posterior portion of body densely scaled, anterior portion probably with 

 few scales above, but none below the lateral line. Pale straw color or 

 pellucid in life with some blotches and specks of olive, about 10 square 

 spots along the back, and about as many along the lateral line, most dis- 

 tinct posteriorly ; top of head dusky ; a small but distinct black spot at 

 base of caudal. Length i inch. (Hay.) Only one specimen known. 

 Pearl River, Jackson, Mississippi; a rather doubtful species, possibly a 

 variation oi Ammocrypta beanii. {vigil, wide awake.) 



loK i-igll, Hay, Bull. U. S. Fish Comm., ii, 1882 (1883), 59, Pearl River, Jackson, Missis- 

 sippi. (Coll. Hay.) 



The genus Ammocrypta represents the extreme of development of the 

 series of darters with elongate bodies, a natural series being formed from 

 Pereina through Hadropierus, Uloceittra, and Boleosoma to Crysfallariu and 

 Ammocrypia. Another well-marked series, at first parallel with these and 

 closely related to its members, leads off from Uadroptcrus and Uloccntra 

 through Etheostoma, culminating in Microptrca. This second series is 

 distinguished as a whole by firmer skeleton with fewer vertebrjv, the 

 skull more convex in cross section, the anal fin smaller and the fin rays 

 tending to become fewer. In habits, the species of the second group are 



