JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, 1890. 



increase inordinately they descend in flights from their permanent breeding- 

 grounds upon cultivated districts where they destroy the crops, lay their eggs, and 

 maintain themselves through one complete generation, but are unable to establish 

 themselves permanently, usually disappearing in the year following the invasion, 

 to be succeeded, after an interval of years, by fresh swarms from the permanent 

 breeding-ground. 



Generally speaking, the life circle of a locust extends through one year, in 

 which period it passes through its various stages of egg, young wingless larva, 

 active pupa and winged locusts, which dies after laying the eggs that are to produce 

 the next generation. The eggs are laid in little agglutinated masses in holes, 

 which the female bores with her ovipositor in the ground. In temperate climates 

 the eggs are usually deposited in the autumn, but in sub-tropical countries, such 

 as India, where there is but little winter, the winged locusts live on through the 

 cold season and only die off after depositing their eggs in the following spring. 

 In this case the eggs hatch after lying in the ground for about a month. In both 

 temperate and sub-tropical regions alike the young wingless locusts, on emerging 

 from the eggs in the spring or summer, feed voraciously and grow rapidly for two 

 or three months, during which period they moult at intervals, finally developing 

 wings and becoming adult. The adult insects fly about in swarms, which settle 

 from time to time and devour the crops. The damage done by locusts is thus 

 occasioned in the first instance by the young wingless insects, and afterwards by 

 the winged individuals into which the young transform after a couple of months 

 of steady feeding. 



In Rajputanaand the Punjab in 1869 the flights were said to have come chiefly 

 from the vast tract of sand hills (Teeburs) between the llunn of Kutch and Bha- 

 wulpore, and partly from the Suliman Range in Afghanistan. Locusts were report- 

 ed as usually to be found in the autumn in the Teeburs, and it would, therefore, 

 appear probable that this tract is a permanent breeding ground, the supposition 

 put forward in some of the reports, that the locusts had flown across from Africa 

 being altogether improbable. On a priori grounds it to be expected that the chief 

 permanent breeding-ground of the flight that invade Sind and Rajputana will be 

 found to be the highlands of Biluchisfcan, or even further to the eastward. The 

 whole question, however, of the permanent breeding-grounds of these locusts is 

 one that requires further investigation. The winged flights appeared throughout 

 Central Rajputana in the latter part of the hot weather, and laid eggs which 

 hatched as the rains set in ; the old locusts dying after fhey had deposited their 

 eggs. From these eggs were hatched young locusts which became full grown and 

 acquired wings in August and September. 



They were said to have laid eggs which produced a second generation in Sep- 

 tember ; but this appears improbable, as locusts in other parts of the world pass 

 through but one generation in the year, though in some cases they produce more 

 than one brood of young. One observer reported that he had seen eggs hatched 

 as early as March in the Punjab, and this increases the confusion. The whole 



