Entomology of the Illinois River. 213 



brown pubescence, especially behind the middle of the 

 segments; diverging till they reach the fifth segment, 

 converging inwardly just back of each false suture; 

 traces of an outer pair of lines present, which at these 

 points curve outwardh'' and become stronger. These 

 stripes are not evident in young larvae. On the posterior 

 portion of each double segment are six black setae on 

 each side, in small bare spots surrounded by heavier 

 pubescence, the bases of the larger ones in a distinct 

 brown or blackish dot. Between the posterior ends of 

 the curves above mentioned is a transverse elongate area 

 containing three of the above setae, the two uppermost 

 close together ; some distance in front of the lower one is a 

 little tuft of pubescence, beneath which is the fourth seta; 

 and on the ventral surface, in line with the transverse 

 area mentioned, is a conspicuous dense daik brown tuft 

 of longer pubescence, half surrounding a bare spot con- 

 taining a long seta, behind which, and one half nearer 

 the ventral median line, is the shorter sixth seta. An- 

 terior divisions with four folds. 



Last segment [Fig. 33] with whitish stigmata! area 

 surrounded by six nearly equal broad fleshy teeth about 

 as long as their basal breadth; a marginal fringe of 

 minute ciliae encircles the area, carried over the margins 

 antl apex of each tooth; upper four teeth pale fuscous 

 within, paler along the middle of each; lower teeth within 

 pale, with a brown longitudinal streak, and an apical 

 seta; three dark dots at base of each; spiracles large, 

 fuscous brown with elliptical blackish centers; often a 

 pair of brown dots between them; exteriorlj^ on lower 

 teeth several setae, backs of upper four nearly bare, with 

 a subterminal and two basal setae. Anal prominence 

 bears six long, whitish, fleshy appendages, a pair each 

 side, about as long as the diameter of the segment, di- 

 rected outwards and backwards when in action, and a 

 shorter pair on their bases beneath, directed backwards. 



Papa [Fig. 34].-Length, ¥ 20-22 mm., d* 18 mm.; 

 ■diameter of abdomen, V 3 mm., d 2 mm. Reddish 



