THE CANADIAN ENTOMOLOGIST 73 



the leathery brown leaves of the bored stem stand out strongly. 

 So one may note the presence of this borer in new territory, even 

 from trolley car or railway train. The principal and only parasite 

 found so far subsisting on this species has not yet been obtained 

 in the imago. There are two or more broods of them surely, since 

 as early as stage four many of the borers have succumbed and the 

 parasites hatched by June 30. The parasitic larva? that mature 

 by August 10 hybernate after spinning up in a tough cocoon. It 

 is an hymenopterous species, with a larva in miniature like that 

 of Sphecius, having pointed, extensile, anterior segments, and at- 

 tacks the host externally. They attain a length of four millimeters, 

 subsist on the juices of the dead host, and mature rapidly, a neces- 

 sity under the circumstances. From two to ten may infest one 

 host, and they spin their flattened, tapering cocoons together in a 

 mass in a nearby portion of the larval tunnel. At a late date in 

 the fall they are yet unchanged to a pupal form. In our rather 

 extended breedings of this group heretofore this parasite has not 

 been encountered with any other species. 



BOOK NOTICE. 



The Bombid.'E of the New World. — Transactions of the 

 American Entomological Society, XXXVIII, pp. 177-480, 

 issued Feb. 4, 1913; XXXIX, pp. 73-200, issued July 17, 1913; 

 22 plates. By H. J. Franklin, Ph. D. 

 That this extensive monograph of the genera Bombus and 

 Psithyrus has taken its turn as one of the regular series of papers 

 published by the American Entomological Society, and has there- 

 fore appeared without any flourish of trumpets, will not obscure 

 the fact that it is not only a work of great merit, recording the 

 author's painstaking investigations into structural and other 

 characters whereby the species of this somewhat difficult group 

 are well separated with the aid of the material at his disposaf- 

 about 5000 North American and about 1000 South American 

 specimens comprising many public and private collections, but 

 also a work that is of especial value to Canadians because of the 

 important position that bumble-bees occupy in the insect fauna 

 of Canada. Of the 47 species of Bombus recorded from the region 

 north of Mexico 37 have been found north of the United States 



