486 PROCEEDINGS OF THE NATIONAL MUSEUM. * vol. 50. 



Acliorutes socidlis is a common species in most parts of Europe. 



Maine. — Orono, February 18, March 6, April 15, May 6, F. L. 

 Harvey. Norway, March 11, May 7, F. Howe, jr. 



Massachusetts. — Arlington, April 12, 15. Behnont, April 19, 

 May 5. Concord, October 16, H. B. Bigelow. Winchester, Febru- 

 ary 9, R. W. HaU. Wellesley, January 28, September 10, A. P. 

 Morse (Cornell Univ.). 



New York. — Center, J. A. Lintner. Karner, April 26, J. A. Lint- 

 ner (N. Y. State CoU.). Otto, J. H. Comstock. 



Pennsylvania. — Osceola, A. D. MacGiUivray. 



Michigan. — ^Agricultural College, May, R. H. Pettit. 



ACHORUTES HARVEYI Folsom. 



Plate 11, figs. 51-58. 



Achorutes harveyi Folsom, 1902a. 



f Achorutes frig idus Axelson, 19056. — (Axelson) Linnaniemi, 1907. 



? Hypogastrura frigida (Axelson) Linnaniemi, 1912. 



Dark indigo blue throughout. Eyes (fig. 51) eight on each side. 

 Postantennal organs (fig. 52) smaller than the eyes, with four (some- 

 times five) peripheral tubercles. Antennae slightly longer than the 

 heq,d, with segments as 10:13:13:20; first two segments subclavate, 

 last two subcylindrical. Olfactory hairs of fourth antennal segment. 

 Sense-organ of third antennal segment consists of two oblong- 

 clavate curving processes. Body elongate, abdomen subfusiform. 

 Unguis (fig. 53) slightly curving, unidentate about one-third from the 

 apex. Unguiculus basaUy suboblong, apically acuminate. One long 

 tenent hair with bent apex. The remaining distal tibiotarsal hairs 

 are usually bent at the tips and often minutely knobbed. Dentes 

 (figs. 54, 55) stout, subcylindrical, apically broad and rounded, 

 bearing dorsally two irregular rows of acutely conical teeth, usually 

 7 to 18 in number. Mucrones (figs. 54-56) almost one-fourth as 

 long as dentes, similar to those of socialis in form. Anal spines (fig. 

 57) two, long (almost as long as the ungues), on prominent approxi- 

 mate papillae; beside each spine is a large hair, apically blunt or 

 feebly knobbed. Clothing (fig. 58) of simple setae. Length, 2.6 mm. 



Achorutes frigidus Axelson is closely allied to this species, with 

 which it may prove to be synonymous. 



Maine. — Orono, F. L. Harvey. Norway, February 23, F. Howe, jr. 



Massachusetts, — Ai-lington, January 16, March 1, 10, 20, April 

 8, 9, 12, 30. 



New York. — Ithaca, April 12, A. D. MacGiUivray. 



Maryland. — Annapolis, January 15, C. E. Munroe (M. C. Z.). 



