66 Journal Xew York Entomological Society, f^'o'- ^^X- 



who in 1855 published a rather extensive paper on the anatomy of 

 the group, and also described and figured some of the more common 

 forms, Simon, who in 1879 gave a description of the species then 

 known to France, and Balzan, who in 1891 published an excellent 

 classification of the pseudoscorpions and described many new species 

 from various parts of the globe, but especially a large number from 

 South America. 



In North America the group has been sadly neglected and prac- 

 tically only two workers have made important contributions to its 

 study. Mr. Nathan Banks has described many species from the east- 

 ern and middle states, and Mr. K. R. Coolidge has published a list of 

 the North American species (see Psyche, December, 1908). Hardly 

 any drawings have been published of our species and there appears 

 to be some confusion in regard to the synonymy of a few of them. 

 On this account and for the purpose of extending our knowledge of 

 the geographical distribution of our forms, and last, though not least, 

 in order to determine the range of variability in our commonest 

 species, Chclifcr cancroidcs Linn., this paper is written. 



The writer's work is based on a large private collection, chiefly 

 from the north central states ; and upon a somewhat smaller though 

 more representative collection in the possession of Cornell Univer- 

 sity. Though the Cornell collection is rather small, yet it contains 

 specimens collected from many parts of the United States. 



In the preparation of this paper the writer is indebted to Professor 

 J. H. Comstock for the privilege of working up the Cornell collec- 

 tion, to Dr. A. D. MacGillivray also of the department of entomology 

 for his many aids, and to Dr. Nathan Banks for comparing several 

 named forms with the types which he possesses. 



Variations in the Habits of ChcUfcr cancroidcs Linn. 



This species varies much in its habits. In Europe it is found 

 chiefly in houses, under wainscoting, under the dry straw and manure 

 of chicken coops, between the loose leaves of old books, in outhouses, 

 etc., and rather rarely under the bark of trees. Menge gives the 

 following account of its habits:^ "Man findet die Thiere selten in 

 Waldern unter Baumrinde, gewohnlich in Hiiusern unter vcrmodern- 



' Menge, A., Ueber die Scheerenspinnen, Chernetids, 1855, p. 31. 



