THE DECTICIN.E (A GROUP OE ORTHOPTEKA) OE 

 NORTH AMERICA. 



By Andkkw Nelson Caitdell. 



Custodian of Oill/opteni, ('. X Xntianid Mascnin. 



The Deoticins^ are a group of locustians which arc readily diti'eren- 

 tiated I)}' their appeai"aiu-e from all other Orthoptera, except certain 

 Stenopelmatinai, The presence of wing-s will usually serve to distin- 

 guish them from the Stenopelmatina^" though they are generally 

 small, especially in the female, where they are sometimes even absent. 

 The presence of two long-winged genera ])reaks into the otherwise 

 compactness of the group, making its exact definition more difficult. 



The members of this group are widely distril)uted over the countr}^, 

 but are more numerovis in the South and West. As a rule the species 

 are local or xqyj rare, but the members of two genera, An<ihr>is and 

 Peranahrm^ especially the former, occur in incalcula))le numbers, 

 doing immense damage to cultivated crops. While most of our 

 Decticina' are probabl}^ primarily herl)ivorous, there is little doubt 

 that many, very likel}' most, of them are at times carnivorous. The 

 cannibalism of A))ahri(S and Peranabru-s is well authenticated, and 

 members of other genera are known to eat other insects as well as 

 individuals of their own kind. 



The life histories of the members of this interesting group are not 

 well known. Such facts as are known regarding the habits and 

 development of the species are given under the discussion of the 

 various forms in this paper. Many of the species are probably noc- 

 turnal or crepuscular in habit, though certain species of some genera, 

 A)uil)rii>i^ Atlantlcus^ etc.. are active during the da}". 



The natural haunts of most of the forrhs seem to be in grassy tields 

 or in open woods, where they hop about in exposed positions, in 

 striking contrast to the habits of Ceuthophiluii and other stenopelmatid 

 forms, which live secluded lives in caves, hollow trees, etc. 



" C'l/phudriTis is the only winged genus of the StenopehiiatiniP found in our Uiiitcil 

 States fauna, though in other regions a number of winged genera occur. 



Proceedings U. S. National Museum, Vol. XXXII— No. 1530. 



285 



