46 COLLEMBOLA OF MINNESOTA 



all directions, and especially in the middle of the back. An- 

 tennae four-jointed, sminthuriform, resembling those of S. Bour- 

 letii Gerv." Harvey, in describing the species which he names 

 "6-maculata," speaks of it as deep blue-black, with four conspic- 

 uous enamel-white spots on the body and two smaller ones be- 

 tween the eyes. The posterior pair of spots on the body some- 

 what reniform in outline, with the sinuses on the dorsal side. 

 Antennae and legs paler, shaded with purple. Antennas slender, 

 nearly two-thirds the length of the body and head, the terminal 

 segment composed of about nine subjoints." Harvey also re- 

 marks : "The species is apparently related to S. quadrimaculata 

 Ryder, but differs in the larger size, broader body, purplish 

 color and white spots between the eyes." 



There is little doubt that the two species are identical. As 

 to color, it is rather difficult on some specimens to be certain of 

 the presence of the pearly spots beside the eyes, yet I am con- 

 vinced that they are always present. Indeed, Ryder's figure 

 shows that he saw white, or at least clear spots in exactly the 

 right position, though he makes no mention of the fact. These 

 particular markings are homologous with those on S. niger, 

 and caused Tullberg to name that species S. bimaculatus, which 

 has since been reduced to a synonym of S. niger. The same 

 spots are likewise present in the allied species : S. minutus and 

 S. aureus, though on these two species, that part of the head 

 being yellow, their pearly color is not very evident. Some of my 

 specimens have the general body color brownish black, which be- 

 comes a light yellowish brown on the legs, while on others the 

 purplish black prevails, in which case the legs are often light 

 purple also. Quite likely Ryder had immature specimens before 

 him, as his description shows them to be both smaller and lighter 

 colored on the back than Harvey's. 



As to the antennae: Ryder's figure shows no indication of 

 subjoints on Ant. IV, yet he speaks of them "resembling those 

 of S. Bourletii/' having, probably, Lubbock's figure before him, 

 in which the antennae are shown almost exactly as in Harvey's 

 figure of S. 6-maculata. My largest specimens measure almost 

 i mm. The furcula and legs are proportionately longer than in 

 S. aureus or S. minutus. The mucrones also is more coarsely 

 serrate, being like that of S. niger, fig. 17. The claws are like 



