40 PHLEBOTOMUS [CH. 



considerable force to a distance at least three times the length of 

 the abdomen. The whole process occupied about two minutes, 

 after which the insect appeared very fatigued and rested for at 

 least three hours before continuing the egg-laying. 



The eggs are almost transparent when first laid, and are 

 covered with a thin coating of sticky substance which causes 

 them to adhere to any surface. They are very elongate in 

 form, dark brown, shining, with longitudinal black wavy lines, 

 which are slightly raised and joined by very fine cross-lines. 

 The length of the egg varies from O'l to 0'i5 mm. (Fig. 22.) 



The incubation period is usually from six to nine days, but 

 the eggs are very susceptible to external conditions and will 

 only hatch if kept in a moist atmosphere. 



1 



Fig- 22. Fig. 23. 



Fig. 22. Freshly extruded egg of P. papaiash. After Newstead 

 Fig. 23. P. papatasii ; adult larva. After Newstead. 



The larva fives in damp earth and is very curious in form. 

 It possesses a large weU-marked head with big jaws, the latter 

 being provided with four distinct teeth. The body is covered 

 with toothed spines that may serve as a protection against 

 enemies, and the posterior end bears two pairs of black caudal 

 bristles. The bristles of one pair are almost as long as the 

 body, whilst those of the other pair are short, but increase in 

 length in the later stages (Figs. 7 and 23). 



The length of the full-grown larva is about 2 • 3 mm. In 

 India the larval stage usually lasts from about three weeks 

 to even as long as two months, but its duration depends mainly 

 on the temperature, being much prolonged in cold weather. 



The larva closely resembles a caterpillar in its movements ; 



