THE AUSTRALIAN MUSEUM MAGAZINE. 



121 



soft ground whether it be suitable for 

 the development of their ott'-spring or 



not. 



The newly hatched larvae from each 

 egg-mass move in a group; when two 

 groups meet they join together into a 

 larger one ajid they build up numl)erH 

 in this way till larval swarms are form- 

 ed. At night the larvae climb plants 

 and pass the time in a state of semi- 

 coma. Next morning, wlien the tem- 

 perature is sufficiently high, the larvae 

 are restored to normal activity, and. 

 ha\ing partaken of breakfast, they 

 again come to eartli, and soon a general 

 movement in one direction is in opera- 

 tion; they do not usually feed during 

 these rambles. ^Vlth the cool of the 

 afternoon the larvae retire to some place 

 of rest on vegetation, and, before pass- 

 ing to a state of repose for the night, 

 they indulge in a full meal. 



If the day remains sufficiently cool, 

 the larvae will content themselves wuth 

 feeding and spending the following night 

 in the same spot. If the weather is 

 moderately warm, the swarm will pro- 

 ceed with its wanderings, but, should 

 the sun be liidden behind a cloud suf- 

 ficiently long to allow the necessary drop 

 of temperature, it will rest once more 

 and possibly feed again; when the cloud 

 has passed and the sun returns the lar- 

 vae start on their march afresh. On 

 very hot days the swarm will often cease 

 travelling during midday and the larvae 

 will cluster close together, hiding from 

 the scorching sun. 



This nomad life goes on until after 

 the final moult, when the locusts become 

 adult and the tribe ceases to wander 

 on foot; for a few days the newly 

 winged insects are incapable of long 

 flights. During this period the locusts 

 devour vast quantities of food and a 

 fatty substance is built up in their 

 bodies. 



When they are fit for flight, one here 

 and there l>egins to take wing for short 

 distances, and one such disturbance, af- 

 fecting other locusts, causes still fur- 

 ther movement until at last the whole 

 swai-m is flying in the same direction. 

 When two flying swarms meet they re- 

 peat the tactics of the lar\'ae by mix- 



ing together; gradually a vast multitude 

 is formed and longer flights are under- 

 taken until at last a definite direction 

 evolves and the locusts desert their 

 breeding region, leaving a few scattered 

 remnants where once they were in count- 

 less numbers. The emigi-ation from the 

 breeding ground is often so complete 

 that only single ones from many groups 

 are left behind, and these are nearly all 

 weaklings or parasitised. 



The migrating adult locust lias its 

 l)ndy cavity largely occupied by air sacs, 

 which are only temporary organs and 

 I'eaoh their highest developiuent at the 

 first period of migration, disappearing 

 towards the last when the developing re- 

 productive ■ organs take their place. 

 Whilst these air sacs are large the in- 

 sects are incapable of taking food in 

 any quantity but subsist on the fatty 

 substance refeiTed to above, and the 

 damage they may do to crops is brought 

 about by their cutting the stems. Later 

 they devour all before them. 



This break in the feeding leaves no 

 trace in the line from their source of 

 dispersal to the site of the damaged 

 crops. Before their breeding localities 

 an(l habits were known the locusts ap- 

 peared to have come from out of the 

 nowhere and ravished the country in 

 one direction. 



It has been a difficult task to track 

 the locusts to their breeding ground, 

 but this has been accomplished and their 

 destruction in the larval fonn has met 

 with success; the migratory locusts are 

 now so well under control in several 

 countries, more pai-ticularly the United 

 States of America and South Africa, 

 that millions of pounds are saved an- 

 nuallv. 



]\Ir. George Milburn, of Nottingham 

 Downs, Queensland, has presented a 

 number of bones, mainly vertebrae, of 

 the extinct, carnivorous, marine reptile 

 Cimoliosaurus. Remains of a smaller 

 species of the same genus have previous- 

 ly been found in an opalized condition 

 in the opal deposits of White Cliffs, 

 New South Wales, but the fossil is 

 known mainly from tlie Cretaceous of 

 Queensland. 



