No. 492] NOTES AND LITERATURE 



799 



ment, and bionomics of the species, is considered especially the ana- 

 tomy of the adult. 



Various species are popularly confused with M. domestica and the 

 author therefore discusses the characters by which this — the true 

 "house-fly" — may be distinguished. External anatomy is then 

 considered and an attempt is made to homologize the various sclerites 

 with those already recognized in the simpler orders of insects. Most 

 of the terms introduced by Lowne are discarded and a number of 

 inaccuracies in his descriptions are corrected. In the discussion of 

 the wincr veins the Comstock-Needham nomenclature is adopted 

 since, "on account of its great morphological value it will no doubt 

 in couR-se of time replace the present confused system." By an over- 

 sight the free parts of M3 and of Cuj are referred to as the medio-cubital 

 and the rubito-anal cross-veins respectively. 



Macroscopic features of the internal structure are described in 

 detail, though there is little discussion of the histological features. 

 Especially detailed are the accounts of the tracheal system, and of 

 the musculature. The four double plates illustrating the anatomy 

 are \yd\ executed, but the plate illustrating the iniagos of Mnsca 

 domestica and related species is too higlily colored. 



The Scf/mriifafioii oj flie hisrrt Head. — Holmgi"en^ discusses the 

 moot question iis to the luinilu r of scoinc-nts in the head of the dipter- 

 ous larva. In opposition to Hrnalsson '!)7 and '05, he maintains that 



'Holmgren, N. Zur Morphologie des Iiisoktcukopfc^. ZooJ. Anz., 1907, 

 Bd. xxxii, pp. 73-97. 



