DE&TRUt //"\ 01 /^ 47 



forest - of Pomerania and Posen tl. 



killed l>\ Empusa a mch quantitii o have 



saved the trees from total destruction. These Entomoph- 

 thora forms are difficult to cultivate artificially, but in l 



■hi cultivated them in Bterilized veal soup, and pre- 

 \ iouslv he experimented w ith i he conidia of En fotnoplii 

 radicam (Fig. 40), applying them to L20 cabl . ater- 

 pillars, with the result that 81 speedily died of the fungus 

 disease resulting. But the most hopeful result-. Forbes 

 thinks, from the artificial cultivation of ble ins< 



cides will attend the use of the muscardine f Botrytis, 



[saria, and Cordyceps), since their Bpores and conidia " have 

 germinated freely again and again in sweetened water, in 

 Bterilized beer-mash, in solutions of % ■■ and of gum, 



and nia\ even grow to some extent in pure water. In 

 these tl and may form its spherical 



conidia in vast abundance; and these have been used with 

 pert r the infection of healthy i 



variet\ ." 



The question has been asked: Cannot we propagate the 

 bacterial insect-diseases and utilize them structive 



agents against insect-pests: Metschnikoff has. sug 

 the feasibility of the cultivation of insect-bacteria, and the 

 application of the cultivated fungus in quantity to places 

 infested by these insects; and several years previously the 

 famous experimenter. Pasteur, recommended to the French 

 Phylloxera Commission to find a means of ring the 



Phylloxera by inoculation with a mi< ic ftu._ 



Balbiani finds that certain Bacilli when inoculated in the 

 blood of other insects kill them. Death follows in from 

 twelve to forty-eight hours, according to i ' temj 



ture. the number and origin of spores, and th 

 and susceptibility of the subject. They die with all of the 

 symptoms which characterize flacherie in silk-worms. 



The practical difficulty in experiments in this direction 

 appears to be that, though the air is rnon with 



floating disease-germs, insects like other animals, and man 



