50 
JOURNAL OF ECONOMIC ENTOMOLOGY 
]Vol. 17 
Tabanus abdominalis Fab. 
aequalis Hine 
americanus Forst. 
annulatus Say 
atratus Fabr. 
benedictus Whit. 
cerastes O. S. 
costalis Wied. 
June, July Never common 
May, June, July June 
May, June, July, August Never common 
May, June, July, August Never common 
April, May, June, July, Au¬ 
gust, September, October Never common 
June, July, August, September August 
May - 
April, May, June, August, 
September 
cymatophorus O. S. July, August 
exul O. S. September 
fulvulus Wied. May, June, July 
fuscicostatus Hine May, June, July August 
giganteus DeG. July, August, October 
lasiophthalmvs Macq. March 
lineola Fab. April, May, June, July, Au¬ 
gust, September 
longiusculus Hine June 
melanocerus Wied. July 
May, June, August 
May, June 
April, May, June, July 
May 
July, August, September, 
October, November 
May, June, July, August 
May, June 
June 
mexicanus L. 
molestus Say 
pumilus Macq. 
sty gins Say 
sulcifrons Macq. 
trimaculatus P. B. 
turbidus Wied. 
venustus O. S. 
August 
Never common 
May 
June 
August 
May and July 
Never common 
June 
April and May 
September 
Never common 
May 
From the standpoint of abundance of individuals, combined with the 
extent of their seasonal occurrence, five of the above species stood out 
from the rest as being the most annoying and harmful pests of stock. 
These were Tabanus costalis , Tabanus fuscicostatus , Tabanus lineola , 
Chrysops obsoletus, and Chrysops vittatus. Adults of these species oc¬ 
curred in abundance from the first of May to the first of September; a 
fact which was true of none of the other species taken. Adults of some 
other species appeared in greater numbers at certain times of the year 
but their attack extended over a more or less limited period. This was 
especially true of Tabanus pumilus which, during the short time in 
which it was abundant, caused more injury than any other species in the 
same period of time. 
President A. G. Ruggles : The next paper is by Mr. Arthur Gibson. 
