December, '13] BRUES STOMOXYS DISTRIBUTION 459 



The Various Stages 



The eggs were not observed in the field but in the insectary they 

 were deposited on top of the ground in masses as shown in figure 11a. 



The individual egg is light yellow in color, oblong in shape and 

 measures .36 mm. in length. 



The larvcv (Fig. 11 6) are found in the ground from three to six 

 inches below the surface and when mature measure from 15 mm. to 

 20 mm. in length. They are i3ink in color and are covered with numer- 

 ous fine hairs which give them a velvety appearance. The three 

 thoracic segments have two longitudinal dark markings on the dorsum. 



The pupoe (Fig. lie) are found in earthen cells in the moist earth. 

 When the pupal stage is first formed they are white; later they change 

 to pink and as the elytra and appendages develop, the}^ change to a 

 dark blue; the eyes are red; abdomen above and below covered with 

 numerous fine hairs that give them a velvety appearance. Dorsum 

 of prothorax also covered with these hairs. The prothorax above 

 square and shaped as in the adult. 



The adults (Fig. 11 d) are dark blue in color with the prothorax, 

 front part of the head and tip of abdomen light brown. First three 

 segments of the antennae brownish, shaded with black. Segments 

 following, black with a small amount of brown at the base. Legs 

 black, shaded with broTVTi. 



Upper and lower side of abdomen covered with fine light gray 

 hairs. Length of body 10 to 14 mm. 



THE GEOGRAPHICAL DISTRIBUTION OF THE STABLE FLY, 

 STOMOXYS CALCITRANSi 



Bt Charles T. Brues 



The common stable fly, Stomoxys calcitrans L., has recently received 

 considerable attention at the hands of entomologists, medical men 

 and veterinarians. It is a nearly cosmopolitan phlebotomic Muscid 

 that has long been a serious pest of domesticated animals and an 

 occasional nuisance to human beings on account of its blood sucking 

 habits. For some time it has been known to act as an occasional 

 carrier for the bacillus of anthrax. More recently it has been shown 

 to be capable of acting as a vector for the virus of acute epidemic 



iContiibutions from the Entomological Laboratory of the Bussey Institution, 

 Harvard University, No. 69. 



