lou 



not at all depressed, sometimes pubescent but in other cases naked. 

 They creep about or burrow in the mud under water. From the 

 structure of the jaws they have been supposed to be carnivorous. 

 The larva3 are greatly flattened and live under rocks, sometimes 

 in rapid currents. 



Stenelmis vittipemiis, Zimmermann. 



(Trans. Am. Ent. Soc. ii, 259, 18G9; Horn, ibid., iii, 40, 1870-71.) 

 Taken in AVillow and Wood Sloughs. 



Macronychus glabratus, Say. 



(Say, Jour. Acad. Nat. Sci. Phil., N. Ser., v, 187, 1827; Compl. 

 Writ, ii, 292.) 



Wood Slough, Aug. 4. Not common. 



Family HETEEOCERiDiE. 



Heterocerus mollinus, Kies. 



This is a small brown pubescent beetle about .20 inch long, 

 with a few irregular yellow marks on the wing covers. 



It occurred in very great numbers in the earth at the edges of 

 the more isolated sloughs, in burrows resembling miniature mole 

 hills. When the seines brought the water over the burrows the 

 beetles at once appeared and took flight. The larvae also were 

 present in abundance, and were found at times exposed on the 

 surface of the water. 



My attention was especially drawn to the curious little mud 

 cases which the larvse construct when ready to pupate, and of 

 which I have seen no published description. The cases are always 

 made in the moist mud at the immediate edge of the water and 

 are carefully detached from the adjacent soil, so that each stands 

 in a little hollow. From one side arises a closed chimnt y often equal 

 in height to the basal portion of the case. The beetles were emerging 

 from the cases on the 11th of August, always making their way out by 

 creeping up the chimney and breaking through its extremity. The 

 beetles were seen along most of the sloughs and lakes. The mud cases 

 were noted as especially abundant along Long and Broad Lakes 

 and Harkness Siough. At the edge of the hrst-named lake eighteen 

 of the cases were counted on an area about one foot squjire. The 

 food of both adults and larvse consists of blown granular matter 

 containing numerous diatoms, and of small cells, isolated and in 

 chaplets, of what Prof. Burrill thinks is a Conferva,— one of the 

 algte which grows on moist surfaces. 



OEDEE TEICHOPTEEA. (Case Fliks.) 



Adults with four membranous wings, the himl ones of which 

 are the broader and are often folded hnigitudinally when at rest. 

 Mandibles rudimentary. Tarsi of five articles. Prothorax a small 



