13^4 MEANS OF PREVICXTION AND CONTROL 



The writer next made experiments in the open field with young insects. 

 With this object he selected localities liable to invasion and distinguished 

 by good climate and abundant herbage. For the purposes of the experi- 

 ments the plots were surrounded by a zinc band, as is done for mechanical 

 methods of control. The bacterial culture was spread over several plots 

 containing young locusts, but without success. In no case was an^^ endemic 

 destruction of the insects observed in consequence of the treatment. Even 

 in one case where 200 insects afterwards placed on the plot were artificially 

 infected, the results obtained were negative. 



The writer draws the following conclusions : 



i) It is not possible to produce in the open field the epidemic infec- 

 tion and the death of young locusts by spra}dng with a culture of Coccoha- 

 cilliis the virulence of which has been increased by successive passages; 



2) It may thus be concluded that this Coccobacillus is a normal in- 

 habitant of the intestine of healthy locusts, and that it only kills the latter 

 when injected into the abdominal cavit}^ ; 



3) By administering this bacteriimi to young locusts with food, no 

 infection is obtained. 



1045 - Spicaria Cossus n. sp., a Hyphomycete isolated from the Larva of 

 " Cossus Rongebois " {Cossus Cossus). — i'ortier j'aul and .Sartory, in Compics 



rendus des seances de la Societe dc Binlogic, Vol. lyXXIX, No. 14, pp. 700-701, Fig. 

 Palis, July 22, 1916. 



In nature, beneath the bark of various trees there are often found in 

 the larval tunnels, mummified larvae of Cossus cossus (i) invaded by a 

 pinkish-white fungus resembling silkworm larvae which have died from 

 " muscardine ". 



On killing a larva of Cossus and keeping it under suitable conditions 

 of humidity, the same pinkish- white fungus is seen to develop in its tissues. 



The writers, who have made a stud}^ of this fungus on several speci- 

 mens of caterpillars taken wild or reared in captivity, describe it under the 

 name of Spicaria Cossus n. sp. 



1046 - A Form of Botrytis bassiana. Isolated from the Larva of the Macrole- 



pidopteron 7Vo/7a^r/a typhae. — I'ortier Paul and SartoRy in Comptcs nndiis 

 des seances de la Societe dc Biologic, Vol. I,XXIX, Xo. 14, pp. 702-703. Paris, July 22, 

 1916. 



The larva of Nonagria ty-phac lives inside the stalks of TypJia laiifoHa 

 devouring the pith. 



On killing one of these caterpillars and keeping it in a sufiiciently moist 

 place, it is seen to mummify and become covered with a whitish coating 

 made up of the fructifications of Botrytis. 



From the morphological point of view, it is not possible to differentiate 

 the Botrytis on Nonagria from B. Bassiana ; on the other hand, the 

 different biological characters which the Authors have been able to 

 ascertain do not appear to them sufficient to constitute the Botrytis on 

 Nonagria a new species. 



(i) See 7^'. Jan. 1913, X" 88 and Jan. 1915, X° 131. Ed.) 



