830 



AN INTRODUCTION TO ENTOMOLOGY 



Fig. 1058- 

 C h r y - 

 sops ni- 

 ger. 



Fig. 1057. — Taba- 

 nus atratus. 



skin and sucking the blood of men and quadrupeds; the females, 

 however, also feed on sweets of plants when they cannot obtain blood. 

 The larger species, as well as some 

 of moderate size, belong to the genus 

 Tabdnus of which nearly two hundred 

 species are listed from North America, 

 cine of the most common of these is 

 the mourning horse-fly, Tabanus at- 

 ratus. This insect is of uniform black 

 color throughout, except that the 

 body may have a bluish tinge (Fig. 

 1057). The species of this genus attack 

 cattle and other farm animals almost exclusively. 

 To the genus Chrysops belong the smaller and 

 more common horse-flies with banded wings (Fig. 

 1058). The species of this genus attack man as 

 well as other animals. To this genus belong the well-known deer-flies 



familiar to fishermen and hunters. Sixty- 

 three North American species of this 

 genus are listed by Aldrich. 



The eggs are deposited in large masses 

 on plants or on exposed stones in the bed 

 of a stream. 



The larvae are aquatic or semi-aquatic. 

 As far as known, they are predacious, 

 feeding on various small animals, some 

 upon snails, others upon the larvee of 

 insects. In most cases they have a single 

 pair of spiracles, which is situated at the 

 hind end of the body; some have a pair 

 of spiracles at each end of the body. 

 Figure 1059 represents a larva of Tab- 

 anus. 



The pupa is not enclosed in the skin 

 of the larva. 



Hine ('03) redescribes all Ohio Species 

 and gives a table of the North American 

 genera. 



Family STRATIOMYIID^ 

 The Soldier-Flies 



Fig. 1059. — Larva of Tabanus. 

 (Photo, by M. V. Slinger- 

 land.) 



The soldier-flies are so called on ac- 

 count of the bright-colored stripes with 

 which some of the species are marked. 

 In the more typical members of this 

 family the abdomen is broad and greatly flattened (Fig. 1060) and 

 the wings when at rest lie parallel upon each other over the abdomen. 

 But in some genera the abdomen is narrow and considerably elongate. 



