126 MORE MINOR HORRORS 



it from the commoner insect. To begin with : 

 it has a hard, firm, chitinous, piercing pro- 

 boscis, which when at rest stretches forward 

 in front of the head, and when in action is 

 pressed down at right angles to the longi- 

 tudinal axis of the body ; then, again, when 



Fig. 38. — Stomoxys calcitransx5. Left antenna right x 1, 

 resting position. (From Graham Smith.) 



resting, its wings diverge; those of the house- 

 fly approximate. Like other flies, the Stomoxys 

 varies somewhat in length, between 5*5-7 mm. 

 The thorax has on its back four longitudinal, 

 dark stripes, broken by a transverse suture ; 

 and, as the accompanying figure shows, the 

 third of the great, long veins which traverse 

 the wing is much more slightly bent than 

 is the case in Musca domestica. Further, 

 whereas the hinder edge of the eye in the 

 house-fly is straight that of the stable-fly 



