Vol. XXV] ENTOMOLOGICAL NEWS 463 



Locust Stridulations * (Orth.). 



By H. A. Allard, U. S. Dep't. of Agriculture, Washington, 



D. C 



In August, 1913, while living at Clarendon, Virginia, just 

 west of Washington, the writer studied the stridulating habits 

 of Conocephalns rohnstus Scudd. This species is very com- 

 mon in the grass and herbage everywhere along the roadsides 

 in this vicinity. Its note is a strong, humming z-z-z-z-z-z, 

 which may continue several minutes without pause. It is 

 considerably louder, more penetrating and droning in quality 

 than the prolonged dry, snappy z-z-z-z-z of Conocephalns 

 triops L., although probably not as strong and penetrating as 

 the z-z-z-z-z-z of C. fusco-striatus Redt. C. rohnstus is scat- 

 tered everywhere along the roadsides, rather than in well de- 

 fined colonies, and stridulates most freely during the dusk of 

 evening and early in the night. 



At Clarendon, Mrginia, the writer also located a small col- 

 ony of Conocephalns exiliscanornns Davis, in a dense thicket 

 of reeds and shrubs near a small meadow. Early in the eve- 

 ning the males advertised their presence by their brisk, vehe- 

 ment lispings, for the notes of this Conocephalns are brief, 

 intermittent and rather soft. This cone-headed grasshopper 

 appears to be strongly gregarious in its habits, as the writer 

 has found it only in small, widely separated colonies around 

 Washington, D. C. Wherever these colonies occur a very 

 striking similarity in the conditions obtains. A thicket of 

 shrubs in low grounds with an undergrowth of grasses seems 

 to be quite indispensable to these interesting locusts. 



In 191 1 (i) the writer described the stridulations of Xiphid- 

 ion strictnm Scudd., from a single individual heard late in the 

 fall. More recently the writer has again studied the stridula- 

 tions of this locust at Arlington, Virginia, and finds, as previ- 



(*Identifications were made by Mr. A. N. Caudell, of the U. S. 

 National Museum.) 



(i) Xiphidion Stridulations. Proc. Ent. Soc. of Washington, Vol. 

 XIII, 1911. 



