16 



of one or two square inches has been thus dotted with single eggs, 

 the rest of the eggs, perhaps half the total number, are deposited in 

 one spot in an irregular mass. The females under observation 

 have always died almost immediately after oviposition and 

 sometimes even before the process was quite completed. . . . 

 The time for hatching varies according to the temperature, from 

 4 to 6 days in the hot weather to 14 days at the end of November 

 at Pusa." 



The larva of Phlebotomus can easily be recognised owing to the 

 presence of long bristles on two tubercles on the last segment of 

 the body (two bristles in the young or four in the nearly adult 

 or adult larva). In Indian species, according to Howlett, these 

 bristles are " often as long as the head and body together, 

 and held conspicuously raised when the animal is walking." The 

 chitinous head, which is totally devoid of eyes, has well- 

 developed mouth-parts, and bears a Y-shaped mark above. 

 The body is cylindrical and composed of twelve segments, which 

 are usually transversely wrinkled ; each segment bears a transverse 

 row of stout spinous hairs. A pair of spiracles are situate on the 

 first and another on the penultimate segment of the body, and 

 according to Grassi, in the larva of Ph. papatasii at any rate, " the 

 segments from the fourth to the tenth inclusive each exhibit on the 

 ventral surface, on the fourth fold, an unpaired protuberance, 

 comparable to the sucker-disc in other Psychodid larvae, which are 

 otherwise very different from those of Phlebotomus." The adulb 

 larvae of the Indian species observed by Howlett are said to be from 

 2 to 3 mm. in length ; those of Ph. papatasii, according to Grassi, 

 measure rather less than 5 mm., are whitish or greyish hi colour, 

 sometimes tinged with yellow, and more or less transparent. The 

 larvae of Ph. papatasii are stated by Grassi to feed on " organic 

 detritus, provided it be not in a state of active putrefaction, and 

 also sometimes on unicellular algae " ; they are very slow in their 

 movements, and the majority of those found by Grassi were 

 concealed by organic debris, which adhered to the dorsal surface. 



As regards the duration of the larval stage and the mode of 

 pupation, Howlett writes of Indian species : " The length of the 



