164 Illmois State Laboratory of Natural History. 



Hydroporus vittatipeiuiis., G. & H. 



(H. lineatus, LeConte, Proc. Acad. Nat. Sci. Phil., vii, 

 296, 1885.) 



Common in Willow Slough. 



Hydroporus consimilis, Lee. 



(LeConte, Agassiz's "Lake Superior," 214, 1850.) 



Very abundant in crannies of decaying and submerged 

 wood in Willow Slough. 



Hydroporus Jiyhridus, Aube. 



( A.ube, Species General des Hjdrocanthares et Gjriniens, 

 573,1838.) 



Common in Long Lake Aug. 9. Also found in Broad 

 Lake and Willow Slough. 



Coptotomus inten'ogatus, Fabr. 



{Dijtisciis interrogatiis, Fabr., Systema Eleutheratorum, i, 

 267, 1801; Crotch, Trans. Am. Ent. Soc, iv, 413, 1872-73.) 



Very abundant in Willow Slough and common in Long 

 Lake and Cedar Creek. 



Acilins, larva. 



This larva is a trifle more than an inch long (1.12 inches), 

 with a fusiform body terminating behind in a pair of short 

 naked caudal stylets. It agrees very closely with the account 

 of a European species {Acilius sulcatus) given by Schiodte. 

 The head is rather small, with two contiguous brownish black 

 spots on the front, and a median spot of this color midway 

 between these and the posterior margin. Sides of head dusky. 

 Segments of thorax and abdomen pale olive above, the scutes 

 of the abdominal segments narrowly edged with black, under 

 parts and legs chiefly white. It differs from the European 

 species in the form of the ligula, which is produced, and fur- 

 nished at its tip with two strong seta3. 



From Cedar Creek, Aug. 8. 



Thermonedes basilaris, Harr. 



(Harris, N. E. Farmer [as cited by Crotch]; Crotch, Trans. 

 Am. Ent. Soc, iv, 402, 1872-73.) 



