110 ENTOMOLOGY FOR MEDICAL OFFICERS 



Adult male. — Like the female, but the palpi are about the 

 same length as the proboscis and have four, or three, white 

 cross-bands. 



Geographical Distribution. — Stegomyia fasciata seems to 

 have been reported from nearly every well-inhabited part of 

 the world between 40° N. and 40° S. It is found in places 

 near the sea-level, and has been taken at an elevation of 

 nearly 3000 feet. 



Habits. — It is everywhere a house-haunting mosquito. 

 According to Boyce, it is "probably the most common 

 mosquito found on ships," though this is not my own experi- 

 ence. Like several other species of Stegomyia, it bites in the 

 daytime as well as at night. Boyce states that he has never 

 found it breeding more than 50 to 100 yards distant 

 from human habitations, and that it breeds in anything 

 and everything that will hold water, even in the heel of a 

 broken bottle or in an old sardine-tin, or in a hole in a 

 rotten tree ; but that it prefers wooden receptacles, par- 

 ticularly water-barrels. 



Eggs. — These are not compacted in a " raft," though they 

 have some tendency to stick loosely together, and are almost 

 black. It is important to remember that the eggs are 

 remarkably resistant, Theobald bred out larvae, in England, 

 from eggs sent from Cuba in a dry test-tube, two months 

 before, and other observers state that the eggs, if kept dry, 

 remain fertile for terms of five to six and a half months. 

 It is also important to remember that the infection of yellow 

 fever can be transmitted through the egg to a second genera- 

 tion of mosquitoes. 



Larva. — The larva is represented in the usual conven- 

 tional position in Fig. 12, the last 2 segments of the body 

 being shown in profile, the rest of the body in a dorsal view. It 

 is dark coloured, and has a rather stumpy breathing-tube and 

 very large tracheal gills. The shaft of the antenna is smooth 

 except for a single hair near the middle and for three or four 

 tiny hairs at the tip, and the terminal joint is minute and 

 truncated. On either side of the 8th abdominal segment 

 (Fig. 21) is a single row of eight or nine scales and a wisp of 

 three small hairs, each scale having somewhat the shape of 

 an arrow-head inverted. The larva is said (probably by 



