THE CANADIAN ENTOMOLOGIST 139 



work on the Diptera of Denmark. The first part, which treated of tlie 

 Stratiomyida?, Xylophagidie, Coenomyiidae, Tabanid;e, Leptididae and 

 Acroceridie, appeared in 1907 ; the second part dealt with the families 

 Asilidje, Bombylidre, Thereoidas and ScenopinidaB, appeared in the follow- 

 ing year, and the present volume forms the third i)art. The work is being 

 published in both the Danish and English languages. The method of 

 treatment of each species is similar to that adopted by Schiner in the 

 "Fauna Aust^iaca," though in many cases it is fuller, especially where 

 bionomic notes are available. The illustrations of anatomical features of 

 value in the determination of the species, and in many cases of the larvne, 

 greatly increase the value of the monograph. The author follows Brauer's 

 classification, as given in the "Katalog der paliiirktischen Dipteren von 

 Becker, Bezzi, Kertesz und Stein." 



The family of Empididi^e is a large one ; about 440 species are 

 recorded from North America and about 675 species from the palcearct'c 

 region ; 1 1 species are recorded as common to both regions. These dark, 

 gray or yellowish flies of a medium to a very small size are generally 

 characterized by their somewhat small, more or less globular head and 

 slender bodies. Many species, especially belonging to the genera E^npis 

 and Rhamphomyia^ are seen dancing in swarms over water and in other 

 places. The phenomena connected with these dances, which are of an 

 amorous nature, are of great interest. Copulation takes place in the air, 

 and in many of the species one may see the males capture a small insect, 

 which, instead of devouring, they carry to the females, and copulation 

 takes place while the female is engaged in eating this love offering. The 

 physiological bearing of these phenomena is not known, but it is certainly 

 worthy of investigation, as in the case of many other insects, such as 

 certain mosquitoes, Hemiptera and Orthoptera, where feeding and 

 reproduction bear a close relationship. As in the case of the adults, the 

 larvse are carnivorous and live in the earth, below leaves, in decaying 

 wood and similar damp and wet situations. Little is known, however, 

 concerning the life-histories of the Empids, but, as a group, they present 

 problems of great interest to the entomologist. — C. Gordon Hewitt. 



Contributions Toward a Monograph of the Bark-weevils of thb 

 Genus Pissodes. By A. D. Hopkins. (Technical Series, No. 20, 

 Part I, Bureau of Entomology, U. S. Dept. Agriculture.) 



This is the first part of a bulletin to be entitled "Technical Papers on 

 Miscellaneous Forest Insects," and is modelled on much the same plan 



