NO. 2134. NORTH AMERICAN COLLEMBOLOUSI INFiECTS—FOLSOM. 493 



Packard's ('73) Achorutes pratorum is simply a color variety of 

 armatus, as I have found by an examination of his cotypes from 

 Orono, Maine, those from Brunswick being absent from the collection 

 in Cambridge, Massachusetts. 



The species referred to Achorutes loletivorus Packard by Gutlii'ie 

 ('03) is armatus, as is evident from his description and from some of 

 his specimens that I have studied. 



Achorutes armatus, one of the most abundant species of its genus, 

 occurs in large colonies in a great variety of situations: under the 

 loose moist bark of logs, on damp soil under wood or dead leaves, 

 midergfound among the roots of grasses or other plants, in moss, on 

 pools of fresh water. This species is the one commonly found on 

 fungi, particularly agarics, though it occm's on Boletus, Polyporus, 

 Morchella, and other genera as well. 



In Massachusetts there are three annual generations and possibly 

 fom*. Dming one season I followed the development of three succes- 

 sive colonies in the same spot (under the bark of an elm log) ; they 

 matm-ed, respectively, late in j\f ay, early in July, and late in August, 

 at mtervals of about six weeks. The species may be fomid, however, 

 in all stages of its growth, at any time from April to October, in Mas- 

 sachusetts. There it passes the winter in the egg. 



Achorutes armatus is one of the most widely distributed species of 

 Collembola. It occurs in aU parts of Europe, in Siberia, Spitzbergen, 

 Greenland, northern Africa (Tripoli), ^Sumatra, Ceylon, New Zealand, 

 Brazil, Paraguay, Uruguay, Chile, and doubtless throughout the 

 United States. 



Maine. — Brunswick, September 10, A. S. Packard, jr. (M. C. Z.). 

 Orono, July, A. S. Packard, jr. (M. C. Z.). Orono, April, May, June, 

 September, F. L. Harvey. 



New Hampshire. — Franconia, Mrs. A. T. Slosson. 



Massachusetts. — Arlington, April 12, June, August 2, September 9, 

 19. Cambridge, March 8, 15, 23 (in a greenhouse on those dates). 

 May 2, 4, 7, 15, June 1, 8, 11, 16, July 16, August 21, 28, September 11. 

 Lexington, May 10, September 18. Waltham, May 3, September 6. 



New York. — Ithaca, April 14, A. D. MacGillivray. Varna, March 

 27, N. Banks. 



Pennsylvania. — Harrisburg, H. A. Smface. 



Ohio.— Salem, March 21, A. D. MacGiUivray. SaHneviUe, Feb- 

 ruary 22, A. D. MacGillivray. Yellow Springs, August 20. 



Illinois. — Urbana, April 13, 30, July 16, August 1, October 15. 

 White Heath, May 8. 



Missouri— Columbia, February, C. II. Crosby. Olden, April 5, 

 E. P. Taylor. 



