152 JOUENAL OF ENTOMOLOGY AND ZOOLOGY 



liaiul. X, p. 4(>. TTzel. Tiitzl)er, k. l)()li. Crcsoll, wiss. TT, ]). 63, 



1891. 

 Is<)to)ii(i pahisfris vav. fused Tiillheri;', k. svon. vet. Akad. liand., 



X, no. 10, ]). 4(;, 1S72. Uzcl. I/itzl)er, k. luih. (U'scll, wiss., II, 



]). 63, 1891. 

 Isotouia hclffagvl Packard, Fifth Rep. Ti-ust Peab. aead., pp. 



33-34, 1873. MacGillivray, Can. ent., XXIII, p. 273, 1891. 

 Tsofoina tricolor (in part) Packard, Fifth Rep. Trust Peab. 



aead., ]). 34, 1873. MacGillivray, Can. ent. XXIII, p. 273, 



1891. 

 Isotoma purpuresceus Packard, Fifth Rep. Trust Peab. aead., 



pp. 34-35, 1873. MacGillivray, Can. ent., XXIII, p. 274, 1891. 

 Tsofo)))a plumhra Packard, Fifth Rep. Trust Peab. aead., p. 35, 



1873. I\IacGillivray, Can. ent., XXIII, p. 274, 1891. 

 IsofouKi pahistris Tullberg, Ofv. k. vet. Akad., fork., XXXIII, 



pp. 34-35, 1876. 



Description: Length — 5-6 mm. Color — Either yellow marked 

 with purple or dark brown. Antennas — Half as long again as 

 the 1iody; IV longest, II and III equal, I shortest. Ocelli — ■ 

 Sixteen. Postantennal organ — Ovate to oval. Claws — Superior, 

 long, sleiider, tapering, armed with two teeth on the inner 

 margin and one on the outer; inferior less than half as long, 

 acute, ajiically curving, armed on inner margin; tenent hair 

 unknobed. Furcula — Half as long as body; denies nearly three 

 times manubrium in length ; mucrones tridentate with the teeth 

 subequal, large, blunt; apical tooth falcate, second and third 

 subfalcate and o])posite eacli other. Integument — Dense, short 

 curving settx?, with long barbellate hairs on the posterior part 

 of the abdomen. 



Variation : There is great variation in this species and I 

 expect to consider this at another time. 



Habitat : Found in great abundance in the entire region from 

 the mountains to the sea. 



Isotouia catena Guthrie 

 (Plate II, Figs. 6-7) 

 Isotoma catena Guthrie 1903. The Collembola of Minnesota, 

 geol. and nat. hist. surv. of Minn. zool. series 4, p. 69. 



