34 DESTRUCTIVE INSECTS OF VICTOEIA : 



be not to stir too deeply, but to scarify and pulverize tlie 

 soil to about the depth of 14 inches. 



The locust plague is a terrible one, as the insects are 

 most voracious, and will tackle almost an3'thing in the 

 shape of vegetation, also other things when hard pressed 

 for food, and no one who has suifered from their depre- 

 dations, or has seen the locusts either at work or in flight, 

 is ever likely to forget it. On the vast plains of 

 Riverina, extirpation would be next to an impossibility, 

 but where the breeding grounds are in our midst, con- 

 certed and energetic action might do a great deal towards 

 a mitigation of the evil. Seasons such as we are now 

 experiencing are favorable to the development of the 

 young insects, but where the newly-hatched locusts have 

 to depend upon dried up herbage for their food great 

 mortality is the result. 



Summary of Experiments with the Locust Fungus 

 Disease at Rochester^ 1899,y7-om Field Observations 

 by Inspector Cock. 



Experiments in the field started on the 12th of October. 

 For three weeks prior to this I had been traversing the 

 northern infested areas, studying the swarms of locusts, 

 and forwarding quantities to Melbourne for indoor ex- 

 periments. Results were unsatisfactory, consequently 

 Mr. French, the Government Entomologist, decided on 

 the field experiments; these I strove to carry out under 

 conditions as near to practical every-day working methods 

 as possible, and infections were made on the 15th and 

 16th, after a fall of 38 points of rain preceded by an 

 unusually dry spell, and followed immediately afterwards 

 by strong dry winds, hot days, and no night dews. 

 Between this and the 23rd three more infections were 

 carried out in the swarms on the open plains, no results 

 showing. On the 23rd, I fenced in 25 square yards on the 



