COLLEMBOLA OF MINNESOTA 91 



I think there is little doubt that the identification is correct, 

 though there seems to be a great disparity in size, mine meas- 

 uring hardly more than I mm. 



The fairly uniform dark bluish color, the "undeutlich" 

 tenent hair, and the similarity of the parts of the specimens to 

 the figures given by Tullberg and Schaffer convince one that 

 either our variety is smaller than that from Nova Zembla, or that 

 I have only immature specimens. As I have taken it but once, 

 the latter may be true. They were found by hundreds in a little 

 bunch on the surface of a little pool at the edge of wave-marks 

 at Lake Pepin, in the latter part of August, 1899. This water 

 habit, alone, would seem to separate them from their closest 

 neighbor A. boletivorus, which nearly always occurs in mush- 

 rooms or occasionallly under bark or rubbish. I have never 

 found it near the water. In this form, which is the slenderer of 

 the two, the manubrium narrows greatly before its union with 

 the dentes, while in A. boletivorus the manubrium broadens rap- 

 idly basal-wards from its very end. For further comparison, see 

 A. boletivorus. 



Achorutes schneideri Schaffer. 

 PL X, Figs. 9-12; XI, Figs. 1-2. 



1896. Achorutes schneideri. Schaffer, Coll. v. Hamburg, p. 173. PI. Ill, 



49- 



1897. Achorutes schneideri. Poppe & Schaffer, Coll. v. Bremen, p. 266. 



"Dark blue, very short haired. Outer claw bearing in the 

 middle a very small, often hardly noticeable tooth. Inner claw 

 suddenly contracted at the middle to a mere bristle. Tibia with 

 one clavate hair, the .swelling at its end not very pronounced. 

 Dentes and mucrones together about as long as the manubrium. 

 Mucrones with narrow plate, end of the edge bowed and pro- 

 jecting out. Dentes three to four times as long as the mucrones. 

 Anal spines small, on very small papillae which are not in contact 

 with each other. Length, 1.7 mm." 



The clavate hair on this species is especially large, reaching 

 out nearly as far as the tip of the superior claw, when bent down 

 that way, but habitually carried out at a wide angle from the claw. 

 The hair is nearly straight. The inner edge of the superior claw 



