408 MEDICAL ENTOMOLOGY 



clinging to the skin under its wings and tail. Some years ago it proved 

 a serious pest in the ostrich farms in Cape Colony ; it was extremely 

 prevalent, and if not removed led to considerable deterioration of the 

 feathers of the birds. 



The female Hippobosca will readily deposit her larva in captivity, but 

 unfortunately it is very difficult to keep the flies alive in cages, and 

 pupae can only be obtained from those which are 

 S sufficiently far advanced in gestation at the time of 

 capture to survive until deliver)-. Many of the larvae 

 of captive flies appear to be deposited prematurely, and do not survive. 



When first deposited the larva is yellowish white with a black cap : 

 it is not capable of any movement. It slowly darkens and the puparium 

 then resembles a seed. The puparium of H. maculata is oval in shape, 

 with the anterior end somewhat flattened and the posterior extremity 

 truncated. Austen describes its structure as follows : ' The puparium 

 'examined is 4*4 mm. in length, by 3'8 mm. in breadth at the 

 ' widest part, and 2 mm. in breadth at the posterior extremity. Rather 

 ' less than 1 mm. in front of the posterior extremity the pupa- 

 ' case is encircled by a shallow groove, marking off a terminal area 

 ' (corresponding to the " black cap " of the larva) which, by means of 

 ' a Y-shaped groove of little depth, is distinctly divided into three 

 ' sections. At the apex of the median triangular section can be seen 

 ' the vestiges of the posterior stigmata of the larva ; the three sections, 

 ' with the exception of a narrow vertical stripe in the centre of 

 ' the triangular one, are covered with low tubercles. On the ven- 

 ' tral side in the median line, immediately in front of the groove, marking 

 ' off the terminal area, is a small pore representing the larval anus. At 

 'a distance of 1'5 mm., behind the anterior and wider extremity 

 ' the puparium is encircled by a second shallow and narrow groove, 

 ' marking the limits of the cap that is split off when the imago 

 ' makes its escape. On each side about 5 mm., from the lateral margin, 

 ' on both dorsal and ventral surfaces, commencing immediately be- 

 ' hind this groove and extending back to a point about 8 mm. from 

 ' the posterior groove, is a series of sharply marked punctures ; those 

 ' in each series on the ventral surface are connected by a deep furrow, 

 ' which is less distinct on the dorsal side. In the specimen examined, 

 ' there appear to be seven punctures in each dorsal row, and six in 

 ' each row on the ventral surface. ' 



It is believed that the females of the genus Hippobosca deposit 

 their larvae on the ground, but it is not definitely -known whether 



