34 CROP PEST COMMISSION OF 



THE Sl'KCIKS OF HORSEFLIES KNOWN TO OCCUR IN 



LOUISIANA. 



3 lost of the species of horseflies thus far taken in the State 

 were collected by Mr. Newell and his assistants, Messrs. Hardy, 

 Garrett, Martin and Flynn, during: the summer of 1905. Some, 

 ho*wever, were taken in former years by Prof. E. L. Moseley, 

 of Sandusky, Ohio, who has a plantation in West Carroll Parish, 

 ai:d a number of specimens have been received from Mr. Charles 

 W. Johnson, of the Boston Society of Natural History. The 

 writer has also collected in the southwestern part of the State 

 in two different seasons. As stated, the species taken belong to 

 two genera, Chrysops and Tdbanus. The first includes the small 

 flies commonly called earflies, woodflies or similar names, whila 

 the latter includes the others, all of which are larger in size. 

 The horseflies proper belong to the genus Tabanus, and are 

 readily distinguished from the species of Chrysops on account of 

 larger size and the absence of small spines at the end of the 

 posterior tibia-. 



CHRYSOPS FLAVIDUS Wiedemann (Brown Earfly). This is per- 

 haps the most common member of this genus on the Louisiana gulf 

 coast, and it has frequently been taken in other parts of the State. 

 The species is almost uniformly brownish all over, but some irregular 

 dark markings are present on the abdomen, and there are four narrow 

 gray stripes on the thorax. The two sexes are much alike, except that 

 in the male the brown markings of the wing are more extensive. The 

 wing in both sexes is brown and subhyaline. 



The following observations made by Mr. Newell serve to give an 

 idea of the importance of this fly: 



"At Cameron, on June 9, 1905, I found a number of specimens 

 inside the slat-work around the cistern at the Gulf Biologic Station. 

 This was about 5 o'clock in the evening. A few were also found on 

 the walls of the Station building and on the outside of the window 

 screens. About twenty specimens were caught. Just after sundown 

 1 went out through the long grass to the beach, and while in the 

 grass plat was attacked by at least a dozen specimens. They do not 

 buzz around preliminary to biting, but sail right in like a hornet, 

 and bite as eoon as they alight. They show no fear when making 

 an attack and can be caught easily when they have once alighted on 

 clothing or flesh. The bite is painful, often followed by a slight 

 swelling and a severe itching. During the middle of the day they are 



