59 



locusts in the southern portion of Santa Fe, and while under the obser- 

 vation of the writer, only four distinct species of locusts were found 

 that had died as the result of its attack. These were the large migra- 

 tory species of Argentina and the neighboring countries, Schistocerca 

 jMrafi ens is Burm. , Zmhioj)od(i f/r rsc/fa 'Sevv . , D qHrnfJiHs coinnrmii s^rxxn. ^ 

 and Dichroplus elongatus Giglio-Tos. It might be of interest, however, 

 to know that each of these, aside from the para/ten-s/'s^ becomes locally 

 destructive at times. This fungus, likeEmpusa, flourishes best during 

 warm, humid weather. 



Having obtained such satisfactor}^ results in transmitting this disease 

 to other locusts while conducting experiments in Argentina, a, quantity 

 of dead fungus-covered insects, like those described above, were 

 gathered and l>rought back to the United States for use in attempting 

 to destroy our North American species. Accordingly, in July and 

 August, 18t>8, large numbers of several of our most common Melanopli 

 were gathered and placed in breeding cages along with a goodly supply 

 of green food and the bodies of the dead fungus-covered insects. The 

 powdered bodies of such dead locusts were also strewn over the food 

 and moistened earth at the bottom of the cages. Jn addition to these, 

 similar experiments were attempted in lields where our native locusts 

 were exceedingly numerous, but in all cases these experiments failed 

 to .show a single instance of the possible transmission of the fungus to 

 our native species. 



More recent attempts at obtaining an artificial growth of this South 

 American locust-killing fungus on various media in the laboratory 

 have likewise proved utter failures, the reason for this being, no doubt, 

 the great age of the material at hand. 



Notwithstanding the failures in the experiments just recorded, this, 

 in the opinion of the writer, is one of the most promising locust- 

 attacking fungi, since it was found to withstand considerable variation 

 in climate and to attack at least four widely dift'erent insects. Then, 

 too, its close relationship with the so-called chinch-bug fungus (Spo- 

 Totrichuiii gloh'ulifenun) gives us some reason for encouragement in 

 the future. 



On July IT, 1900, a letter was received from Mr. George W. Martin, 

 Sterling, Colo., who had undertaken some experiments with the South 

 African* locust fungus, a supply of which was furnished him from 

 Washington. This letter reads as follows: 



Deak Sik: I have succeeded in killing a large number of grasi^hoppers on 60 acres 

 of alfalfa, covering the ground with them for one-fourth mile. The disease is still 

 spreading and is now 500 yards from where the infected ones were placed. I do not 

 see why it will not kill all of them. I use corn meal, 2 parts sugar, 1 part, for dose, 

 feeding at 4 p. m., again 6 p. m., putting them out at 7. I drive over the fields to be 

 infected. The fungus seems to be better a week old than earlier. 

 Yours, truly, 



Geokge W. Martin. 



