COLLEMBOLA OF MINNESOTA 61 



"Under rubbish and the loose bark of stumps, also on agar- 

 ics and boleti. Found under boards as late as November, prob- 

 ably hibernating there. Common in Maine." 



This is our most common species in Minnesota, often oc- 

 curring with P. maculosus, which it much resembles in anatom- 

 ical details. Harvey mentions no inner denticle on the inferior 

 claw. He may have overlooked it, as it certainly shows on all 

 my specimens. 



Orchesella albosa n. sp. 

 Plate I, Figs. 14, 15. 



Yellow or white in color, antennae more or less purplish, 

 shading evenly out to tip of Ant. VI, which is darkest of all. 

 Sometimes the antennae are almost entirely yellow, excepting 

 the dark distal end of Ant. III. The body is comparatively 

 shorter than in O. zebra, and the antennse longer, the ocelli also 

 differ in being relatively smaller and farther apart. Perhaps, 

 as the lighter coloring indicates, this is more of a dark-loving 

 species, and the tendency is toward a reduction in the size of the 

 ocelli on that account. In respect to the character of the claws, 

 furcula, etc., it resembles O. zebra, but I believe it is the only 

 species of Orchesella recorded, in which neither bdy nor legs 

 show color markings. Length, 2.5 mm. Found under boards 

 near Minneapolis. Not common. 



Orchesella zebra n. sp. 

 PI. I, Figs. 8-13; XVI, Fig. i. 



Form elongate. Color, dark purple and yellow. Along the 

 median dorsal line is a dark stripe, sometimes narrowing to a 

 mere line or entirely broken, again broadening out into almost a 

 cross-band on Abd. Ill and Th. III. Two lines of longitudinal 

 spots situated dorso-laterally on all segments except the pro- 

 and meso-thorax, constitute another series of markings, while 

 the body markings are completed by another such line of spots, 

 only larger and more widely separated, situated laterally. The 

 head has a black band connecting the eyes, but no other color 

 markings. Eyes black. The ocelli are larger in proportion to 

 the eye spot, and therefore closer together than in the case of 



