110 MISC. PUBLICATION 631, U. S. DEPT. OF AGRICULTURE 



Figure 57. — Mature larva, ventral view: A, Hypoderma diana ; B, H. lineatum. 

 (After Cameron {23, p. 137).) 



HYPODERMA BOV1S (Linnaeus) 



The Northern Cattle Grub 



Recognition Chabacters. — Adult : This is a dark, rather robust bumblebee-like 

 fly, about 12 mm. in length. The head and thorax are clothed mainly with 

 golden-yellow hairs except on the mesonotum behind the suture, where the 

 vestiture is black, the black background showing through to form a prominent 

 cross band. The mesonotum bears four polished longitudinal stripes, broadly 

 interrupted at the suture. The abdomen is clothed with long yellow hair which 

 becomes reddish toward the apex. The femora are mainly black, the tibiae 

 brown, and the tarsi yellowish brown. Larva : The stages are sufficiently 

 characterized in the keys. 



Geographical Distribution. — Nearctic Region: Canada (all parts; specific 

 records from Nova Scotia, Quebec, Ontario, Manitoba, Saskatchewan, Alberta, and 

 British Columbia) ; Maine, New Hampshire, Vermont, Massachusetts, Connecti- 

 cut, New York, New Jersey, Pennsylvania, Delaware, Maryland, District of 

 Columbia, Virginia, Ohio, Michigan, Indiana, Illinois, Wisconsin, Iowa, North 

 Dakota, South Dakota, Nebraska, Montana, Wyoming, Oregon (also from cattle 

 imported into Florida, Texas, and Alabama ) . Neotropical Region : Puerto Rico 

 (from imported cattle), Jamaica (on imported cattle), Brazil (questionable 

 record), Chile (on imported cattle; unable to develop). Palaearctic Region: 

 Ireland, Scotland, Wales, England, Spain, France, Netherlands, Switzerland, 

 Italy, Sicily, Norway, Sweden, Finland, Denmark, Germany, Poland, Austria, 

 Rumania, European Russia, Morocco, Algeria, Libia, Egypt, Cyprus, Kazak, 

 Siberia (Tomsk), Inner Mongolia, China, Manchuria. Ethiopian Region: South 

 Africa (on imported cattle; unable to develop). Australian Region: New Zea- 

 land (recorded, but not established). 



Life History and Pathogenesis. — The normal hosts are cattle. 

 Eggs are laid singly ; the greater activity necessary for such deposition 

 produces a high pitch of excitement among the cattle. The eggs hatch 





