February i?^q] 



rSYCHE. 



323 



on and confirmatory of geological 

 clianges. For these reasons and those 

 noted at the beginning, viz. — wide 

 distribution, terrestrial and conspicuous 

 habits, numerical abundance, size, etc. 

 — the family and its distribution is of 

 high importance in a study of life zones 

 in their relation to agriculture and of 

 faunal regions in their relation to general 

 science. 



In conclusion, while tiie evidence 

 here presented is drawn largely from 

 personal experience, I wish to acknowl- 

 edge my indebtedness also to Messrs. 

 Scudder, Henshaw, Beutenmiiller, 

 McNeill, Harvey, and otiiers through 

 data furnished by their publications, 

 collections, or notes of various kinds. 

 Owing to the total lack of data from 



broad portions of the district it is mani- 

 festly impossible to draw definite boun- 

 daries at present for tiie faunal areas 

 of locust-distribution, and I am under 

 great obligations to Mr. Scudder for 

 permission to reproduce from his 

 faunal and climatal map those portions 

 and features most desirable for exami- 

 nation in this connection. The termi- 

 nology used, in a few cases now need- 

 ing revision, is, for convenience, the 

 same as that in my " Notes on New 

 England Acridiidae" (Psyche, Oct. 

 1S94 to Dec. 1S9S), which contain 

 fuller details — seasonal,, physiographi- 

 cal, and geographical — of the distri- 

 bution of each species in New England 

 than can be given in the limits of this 

 sketch. 



POSTSCRIPT OX PERDTFA. 



I have now before me mounted heads of 

 P. semicrocea, which is the nearest to Smith's 

 typical species I have seen, and of P. rci- 

 besinae which is a typical Cockerellia. The 

 actual palpal differences are as follows : — 



P. femicyocea. Labial palpi with the first 

 joint about or hardly as long as the other 

 three together; second longer than third or 

 fourth, which are about equal to one another. 

 Maxillary palpi with the last three joints 

 about equal to one another, and longer than 

 first three. 



P. verbesiaae. Labial palpi with the first 

 joint about or over twice as long as the other 

 three together; the other three subequal, 

 but the third the shortest. Maxillary palpi 

 with the first joint longest, the others about 

 equal to one another, except that the second 

 is shortest. 



I must admit that there is more difference 

 than I had supposed. 



T. D.A. Cockerell. 

 Mesilla Park, Noz'. 7. 



RECENT LITERATURE. 



Three entomological works of a more or 

 less popular character have been issued 

 recently and demand brief notice. 



The readers of Psyche are well .icquainted 

 with the careful observations of the habits 

 of insects made by Mr. and Mrs. Peckham of 

 Milwaukee. The State of Wisconsin has 

 now published a volume by them on the 

 instincts and habits of the solitarv wasps. 

 It is replete with interest and merits unquali- 

 fied praise. The care, patience and assiduitv 

 of the authors in following the study of tlieir 

 little friends to the minutest details of their 

 daily life and by night as well as by day, has 



