50 COLLEMBOLA OF MINNESOTA 



though I have taken it out of doors as well; where it occurs 

 throughout the summer months under damp boards and drift- 

 wood, in low, moist woods. It is an active species when touched, 

 but much more easily caught than eyed species. Ant. IV is 

 slender and well haired, especially toward the end. It is distinctly 

 ringed. The legs are unusually long and slender. The claws 

 are long and slender, especially so on the first pair of feet, fig. 4. 

 A peculiarity of the furcula is to be found in the presence of 

 two stout spines, probably originating from hairs, which are 

 borne by the distal ends of the dentes at their outer sides, fig. 

 2 ; smaller ones are found farther up on the dentes, on the inside. 

 The sub-anal papillae, fig. i, are not slender, but short and bunch- 

 like; and the bristle is nearly straight, appearing narrower than 

 in most species, and less branched, if at all. The reddish-brown 

 spots which appear under a low magnifying power, are seen upon 

 greater magnification to be clusters of many exceedingly minute 

 pigment dots. Older specimens show more pigmental color than 

 do younger ones. The clearness of the body makes it an espec- 

 ially favorable species for the study of the muscles in situ. 



Although occasional individuals have been found, yet the 

 species was taken in abundance on one occasion only. On March 

 27, 1901, I found them in abundance on a small island in the 

 Mississippi River below Red Wing, Minn. 



Sminthurus curvisetis n. sp. 

 PI. Ill, Figs. 1-7. 



Dull black above ; around the eyes, under side of anal seg- 

 ment and two low lateral spots just in front of the base of the 

 manubrium, yellow. Antennae, legs and furcula dark blue. The 

 back is sparsely set with strong, truncate, backward-curving 

 spines. Antennae slender, with segments increasing progres- 

 sively in length and decreasing in breadth custally ; of a 

 purplish blue throughout. Legs rather stout, claws stout, 

 unarmed, the tip of the inner claw bearing a strong, clavate 

 hair which slightlv overreaches the end of the lareer 



-> o 



claw. Tibiae without clavate hairs. Furcula rather stout; 

 manubrium about as long, measured ventrally when extended, 

 as the dentes and mucrones together ; dentes tapering 



