Entomology of the Illinois River. 209 



Anal prominence broadly tuberculate or with a short 

 horn each side. Lower stigmatal teeth small, dis- 

 tant from the four above. Setae of posterior divi- 

 sions about equidistant. [Fig. 36, 37, 39.] 

 A pair of acute fleshy teeth anterior to the outer 

 pair of stigmatal teeth; anal prominence quadri- 



tuberculate Larva {a). 



No teeth anterior to the stigmatal ones. 

 Upper four teeth very long and acuminate, the 

 ends overhanging stigmatal field ; anal prom- 

 inence with a large thick acute horn each side. 



Aquatic. [Fig. 36.] Larva (J). 



Upper four teeth straight or recurved; anal prom- 

 inence broadly tuberculate. Terrestrial, 

 Inner pair of teeth above not longer than outer 

 pair, pale on anterior face. 

 ' No black on four upper teeth except sometimes 

 at their bases. 

 Teeth all pale except a black dot at tips of 

 lower pair; outer twice the length of in- 

 ner pair Larva (c).* 



A black stripe at base of inner teeth and 

 often a black line on base of outer teeth; 

 upper face of lower teeth broadly black. 



Larva ((^).t 



•This larva, taken from amongst the roots of wheat near Urbana May 4, is shrunken 

 by alcohol, but quite a distinct species. 



Length about 15 mm. D;irk fuscous, pubescence scarcely visible, indicated by 

 short microscopic transverse lines; folds distinct, three impressed lines on anterior 

 ■divisions; usual setse present. Upper stigmatal teeth whitish posteriorly, their tips 

 rather slender and pointed, the outer pair about twice as long as tlie inner pair- 

 lower teeth distinct, whitish, a minute black ring at tip, and a piir of brown dots 

 at their bases; some dots between the stigmatal plates, the latter no: distant. Anal 

 prominence with two broad tubercles below the anal opening, and a pair of lateral 

 tubercles. 



tThis was also collected near Urbana, under the bark of old logs in woods, and 

 seems to be quite common there. The specimens examined were collected April 6 and 

 12. 



Length 25-30 mm., diameter 3.5 mm. Transverse pale line of head rather broad. 

 Yellowish dusky, pubesoencc distinct, transvi'rse arrangement well marked; 

 folds of segment evident; middle one of posterior divisions bearing above and below a 

 narrow low transverse darker ridge upon whii-h are ihe usual four setae. Upper teeth 

 of last segment nearly equal in length, tlie outer pair distinctly thicker and less acute, 

 inner pair with a lunate-trian.;ular black spot; at base of each; apes of lower teeth 

 white, remaining upper surface broadly black or dark brown in subquadrate form. 

 Stigmata large, black, not distant. Anal prominence with a lateral and inferior pair 

 of broad tubercles. 



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