196 FISHES OF ILLINOIS 



continuous with the caudal except for a shallow notch, while these 

 fins are wholly separate in the other catfishes. According to Dr. 

 Jordan, it lurks habitually under stones and logs. Dr. Eigenmann 

 reports that the eggs of this species were laid, in Turkey creek, In- 

 diana, in the latter half of June, in depressions under boards, and 

 that they were apparently watched by the adult. The young re- 

 main for some time in the nest after hatching. 



Genus SCHILBEODES Bleeker 



Body more or less elongate, subcylindrical anteriorly, the tail com- 

 pressed. Head less depressed than in Noturus. Skin rather thin, very 

 finely villose or almost smooth. Supraoccipital bone free from head of 

 second interspinal. Teeth subulate, in broad bands, the band of upper 

 jaw abruptly truncated at each end as in Ameiurus (without lateral 

 backward extensions as in Leptops and Noturus). Adipose fin long and 

 low, connected with the accessory rays of the caudal, from which it 

 may or may not be separated by a notch. Caudal fin obliquely trun- 

 cated or rounded, with numerous rudimentary or accessory rays both 

 above and below caudal peduncle. Anal fin short, its rays 12 to 23. 

 Ventrals much rounded. A poison gland present beneath the epidermis 

 surrounding base of pectoral spine. 



Key to the Species of SCHILBEODES found in Illinois 



a. Pectoral spine entire behind or only slightly roughened near base ;* adipose 



fin continuous with caudal, the notch being absent or faint, never acute. 



b. Jaws equal; anterior and posterior edges of pectoral spine entire, or the 



anterior edge very slightly roughened near tip; color purplish olive to dark 



brownish, without noticeable specking; three dark streaks on sides 



gyrinus. 



bb. Lower jaw included; pectoral spine entire in front or with 1 or 2 obscure 

 points near tip, entire or weakly toothed near base behind; color dark 

 brown to blackish, flecked rather coarsely with darker; dorsal, anal, and 

 caudal fins pale-edged nocturnus. 



aa. Pectoral spine with distinct posterior serrte, which are recurved and in 

 length more than \ the diameter of spine; notch between adipose and 

 caudal fins always more or less acute. 



c. Pectoral spine short, 3 in head, the posterior serrae not £ diameter of spine; 



notch between caudal and adipose fins usually shallow; color light brown, 

 sometimes faintly mottled; a large squarish spot of lighter color on back 



before dorsal and a smaller crescentic one behind it exllis. 



cc. Pectoral spine longer, less than 2 in head, its posterior serrae strong and in 

 length nearly equaling diameter of spine ; notch between adipose and cau- 

 dal fins deep and acute; color grayish with black specks and larger 

 blotches; 4 saddle-like blotches on back, the last but one extending upon 

 adipose fin to its edge miurus. 



* Arkansas specimens of S. nocturnus have a few short, sharp teeth near base 

 behind (Jordan). 



