57 



nothing will do so. Even had the insects which were collected and 

 buried been killed by poison, boiling- water, heat, or in some other 

 violent manner, and treated in a similar wa}'^, the result would in all 

 probabilitj' have been quite similar. But when these insects die from 

 disease and drop to the ground in a variet}' of localities, and later are 

 gathered together, there is no telling how many different kinds of 

 saprophytic fungi may have come in contact with and adhered to them. 

 Even Empusa-killed insects, attached to vegetation a considerable dis- 

 tance from the ground, would themselves become infested, and under 

 favorable conditions support a great variety of these molds. 



In our experiments with the fungus mentioned in this paper as 

 3fucor raceiiiosusy^^h^vQ found that such locusts as have been dipped 

 or sprinkled with sugar- water cultures of it are killed; but when 

 turned loose in the field there is no apparent spreading of the fungus 

 to other 'hoppers. Neither did we have any success in d(\stroying 

 them Avhen the inoculation was attempted by feeding the fungus to the 

 insects along with bread crumbs, etc., that had been used for culture 

 media. It is surmised that by thus dipping the insec^ts into the liquid 

 containing the fungus some of the mycelial threads and spores of 

 the latter enter the stomata, as well as the sutures l^etween the rings 

 of the abdomen and thorax, and start to grow, and in a short time use 

 up the fluids and vital tissues of the body sufficientl}" to cause death. 



Since none of the other fungous diseases of locusts, aside from that 

 caused by E^npusa gvylU., seem to have received much attention 

 heretofore, it has been thought best to devote some space to their dis- 

 cussion here. Especially does this seem warranted because of the 

 numerous references made to them in these pages. 



SPOROTRICHUM Sp. 



The first of these other locust-attacking fungi that deserves mention 

 was discovered by the writer in 181>7 while investigating the destruc- 

 tive locust problem of Argentina, South America. In the month of 

 June, when the insect then under in\ estigation was hibernating, or, 

 more correctlv speaking, resting, and confined chiefly to the more 

 northern districts of that country, it was thought best to occup}' the 

 time in gathering data of various soils. It was on one of the field 

 excursions which were regularly made at intervals, as this work Avas 

 progressing, that dead fungus-covered nymphs of thc^ destructive 

 locust were discovered securely tucked away in dense bunches of a 

 species of grass common to a large portion of the open country. 

 These dead saltcmas (as the nymphs of these insects are called in that 

 country) had evidently been destro3^ed by the fungus in large numbers 

 during the previous 3'ear. Still, so securely were the}^ tucked away 

 in these clumps of grass that fully eight months later they not only 

 remained nearl}^ perfect in form, Init also retained their colors sufli- 

 ciently to make their identit}' certain. 



