252 ECONOMIC ENTOMOLOGY 



more or less cylindrical in shape, provided at the posterior end with a 

 disk-like sucker fringed with hooks wherewith they attach themselves 

 to the rocks. At the anterior end are two fan-shaped organs for secur- 

 ing food, and behind these on the ventral side is another sucker. The 

 pupa is formed within a boot-shaped cocoon, and is provided with two 

 tufts of respiratory filaments on the thorax. 



As a rule there are two or three broods in a season. The most 

 abundant species in the northeast are Simulium venustum, S. vittatum 

 and S. hirtipes, on the western Canadian prairies S. similis Mall. 

 S. pictipes is innoxious. 



Control. — Smudges and fumes of pyrethrum as repellents; destruc- 

 tion of larvae by phinotas oil. 



CHIRONOMIDiE (MIDGES) 



{Ceratopogon spp. {Punkies). — These minute flies, known as "pun- 

 kies," ''no-see-ums" and ''sand-flies," are also very troublesome pests in 

 northern woods. They are blood-suckers and attack any exposed 

 part of the body. The larvae are thread-like and live in water or 

 in moist places. Dr. Riley states that the following species bite: 

 Culicoides guttipennis, the most common form; C. cinctus, C. sanguisuga, 

 C. stellifer, C. variipennis, and C. unicolor. Not much, however, 

 is known regarding the habits of the difi'erent species. 



TABANIDiE (HORSE FLIES, BULLDOGS, CLEGS, BREEZE FLIES) 



Common Genera: 



A. Hind tibise with spurs at tip; third segment of the antennae with five rings; 

 second segment but little shorter than the first; wings with dark markings. 

 — Chrysops. 

 AA. Hind tibiae without spurs; third segment of the antennae with a well- 

 developed process. — Tabanus. 



(Consult "Tabanidte of Ohio" by Hine) 



Black Horse Fly {Tabanus atratus Fab.). Adult. — A large fly with 

 broad and slightly flattened "body and large and depressed head; last 

 segment of antennae annulate and without stylet; females with power- 

 ful piercing mouth-parts (see p. 8); may transmit disease (Fig. 158). 



Eggs. — Elongate, spindle-shaped; laid in large black masses of 500 

 on the leaves of grasses, sedges and other plants in marshy ground. 

 Hatch in less than 9 days. 



