466 ENTOMOLOGICAL NEWS [Dec., '14 



rotundifolia and uhleri; and in colonies of Oecanthus and 

 Conocephalus species. 



From a study of the stridulatory habits of various musical 

 Orthoptera it has been learned that some species voluntarily 

 change their notes from time to time. This is true for Scud- 

 deria te.rensis, Scudderia fnrcata, Arnblycorypha rotundifolia 

 and A. uhleri, so far as the writer has observed. An abrupt 

 change by one male is very likely to call forth similar responses 

 from other males within hearing. Just what these volitional 

 modifications signify in the social relationships of the species 

 is not clear. 



It is quite plain, however, that stridulation in one way or 

 another has become intimately associated with the mating 

 activities of the musical Orthoptera. Throughout the lives of 

 the males the greater part of all attention and interest is con- 

 cerned with' courtship and stridulation. Although the noisy 

 performances of one male may excite and attract another, as 

 it would seem in many instances, this simply means that the 

 courtship of the female is the ultimate aim in the life of every 

 male. Stridulation thus serves to bring more than one male 

 within the immediate society of the female, and at the same 

 time tends more or less toward community aggregation for 

 many species. 



A Mite Gall on Clementsia (Acarina). 



The Red Orpine, Clementsia rhodantha (Gray), is a Crassulaceous 

 plant which abounds at high altitudes in the Rocky Mountains. On 

 July 7, 1914, I found it at timber line (about 11,200 feet alt.) on the 

 side of Mt. Martha Washington, Colorado, and observed that most of 

 the heads, instead of producing the normal pink flowers, were aborted 

 to a dense round mass of a dark crimson-lake color, consisting of 

 excessively tuberculated floral parts, inhabited by an Eriophyid mite. 

 In Central Europe and Italy a similar deformation of Rhodiola rosca 

 is produced by Eriophycs rhodiolae (Canestrini) ; and judging from 

 the brief accounts given by Nalepa and Houard, it seems very prob- 

 able that we have to do with the same species of mite. The number 

 of cross-lines is about the same, and the only apparent discrepancy 

 T note is in the great length (about 65 microns) of the first ventral 

 setae (Nalepa says they are "mittellang"). I have not access to Cane- 

 strini's figures. T. D. A. COCKERELL. 



