UNITED STATES DEPARTMENT OF AGRICULTURE 



ft BULLETIN No. 329 



Contribution from the Bureau of Entomology 

 L. O. HOWARD, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



March 6, 1916 



NOTES ON FIVE NORTH AMERICAN BUFFALO 

 GNATS OF THE GENUS SIMULIUM. 



By Akthur W. Jobbins-Pomekoy, 1 Entomological Assistant. 



CONTENTS. 



Page. 



Introduction 1 



The adult stage 2 



The egg stage 11 



The larval stage 12 



The pupal stage . 23 



Page. 

 Life cycle and number of generations- 26 



Insect enemies and parasites 27 



Simulium as a possible carrier of dis- 



ease__ 28 



Bibliography 35 



INTRODUCTION. 



Certain speeies of the insects known as "buffalo gnats" are im- 

 portant enemies of man and domestic animals in the United States 

 as well as in other countries. Although the principal area of abund- 

 ance in North America is in Canada and the Northern States, out- 

 breaks of pests of this group occur as far south as Louisiana and 

 Florida. While they are dependent upon running w T ater for develop- 

 ment, they make use of very small streams and, to some extent, of 

 irrigation ditches, and are consequently found occasionally in con- 

 siderable numbers in the drier parts of the country. 



About 20 years ago buffalo gnats attracted great attention along 

 the lower Mississippi River. They frequently became so abundant 

 that plantation operations were stopped on account of very painful 

 attacks against live stock as well as human beings. These great 

 outbreaks were due to conditions established by the overflow of the 

 Mississippi River. The perfection of the levee system has changed 

 these conditions so that the outbreaks are less frequent and of greatly 

 reduced severity. Nevertheless, these insects are still abundant 

 enough to be considered a pest in the Mississippi Valley as well as 

 in many other portions of the South. 



The damage done by buffalo gnats results from their painful bites 

 and the loss of blood which ensues. When they are abundant they 



1 Resigned Nov. 20, 1914. 

 Note. — This paper is of Interest to persons living east of the Mississippi Eiver. 

 10981°— Bull. 329—16 1 



