300 FISHES OF ILLINOIS 



ecological preference, this little species thus separates itself 

 notably from its nearest ally. 



Described originally from Illinois specimens, it has since 

 been found from Indiana and Iowa to Alabama, and southwest 

 to the Angelina River in Texas. 



Females distended with eggs have been taken by us late 

 in May. 



Genus CRYSTALLARIA Joedan & Gilbert 



Body slender, elongate, subcylindrical, pellucid in life; mouth small, 

 horizontal; premaxillaries not protractile; teeth on vomer; vertebrae (C. 

 asprella) 47 (23 + 24) * ; pyloric caeca 3* ; belly naked or with a few ordinary 

 scales. In its protractile premaxillaries, as well as in habit, resembling 

 Hadropterus, but the body hyaline in life as in Ammocrypta. One species 

 known, a darter of rather large size, first obtained by the senior author in 

 Hancock county, Illinois. 



Genus CRYSTALLARIA ASPRELLA (Jordan) 



Jordan, 1878, Bull. 111. State Lab. Nat. Hist., I. 2, 3S (Pleurolepis). 

 J. & G., 490 (Ammocrypta); M. V., 123 (Etheostoma) ; B., I, 104; J. & E., I, 1061; 

 F., 66 (Ammocrypta); L,., 28. 



A slender species, with extremely small scales, and pellucid in life. 

 Easily known by these marks and by the peculiar broad saddle-like bands 

 across the back, which are continued obliquely downward and forward to the 

 lateral line in this species. Length 3 to 4 inches; body very long and slender, 

 not at all compressed, being nearly uniformly cylindrical from nape to front 

 of second dorsal; depth 7.8 to 9 in length; caudal peduncle very slender, its 

 depth 3.7 to 4.7 in its length. "Color hyaline-olive with 3 or 4 dark, broad 

 cross-bands meeting over the back, the width of the first 3 about equal to 

 depth of body, the fourth narrower, and all extending somewhat obliquely 

 downward and forward to the lateral line; a dark lateral band along side, 

 made up of about 10 more or less confluent dark quadrate blotches, darkest 

 where it crosses through the cross-bands" (Jordan and Evermann). "In life 

 the oblique bands are of a golden, iridescent color; cheeks below eye bright 

 iridescent silvery; pupil black with brassy rim; iris chiefly dusky; spots on 

 sides dusky with traces of golden between" (H. Garman). Head 3.7 to 4.5, 

 its width 2 to 2.3 in its length; interorbital space very narrow, concave, 8.3 

 to 9.7; eye somewhat elliptical, 3.3 to 3.9 in head; nose decurved and broadly 

 rounded anteriorly, somewhat shovel-shaped, 2.6 to 3.2 in head; mouth rather 

 broad, subterminal, the maxillary not reaching to front of orbit; cleft 3.5 

 to 3.9 in head; lower jaw included; gill-membranes only slightly connected, 

 distance from muzzle to angle usually less than to back of orbit. Dorsal fin 

 XII or XIII, 13-15; soft and spinous portions separated by a distance almost 

 equal to diameter of eye; spinous dorsal high in front; height of first dorsal 

 1.8 to 2.5 in head, second 1.7 to 2.2 (height of first 82 to 105 per cent, of 

 second); caudal lunate; anal I, 13 or 14; pectorals 1.1 to 1.3 in head; sepa- 



, * In a single specimen (Accessions No. 27670, III. State Lab. Nat. Hist.). 



