134 



to determine the best method of control of E. nigroaenea, but meantime 

 the following recommendations are given. In North America a dry 

 spray, made of a mixture of 1 lb. Paris green, and 20 lb. calcium 

 sulphate, is applied in the morning while dew is still on the plants. 

 A wet spray of | lb. Paris green, 40 gals, water, and \ lb. slaked lime, 

 or 2 to 3 lb. lead arsenate dissolved in the same quantity of water, is 

 recommended. As Bordeaux mixture is a remedy for the fungus 

 disease which often appears simultaneously with the insect, a good 

 control is a combination of Bordeaux mixture and arsenic, consisting 

 of sulphate of copper, 6 lb. ; slaked lime, 6 lb. ; water, 40 gals. ; to 

 which is added a mixture of 40 gals, water with 8 oz. Paris green or 

 3 lb. lead arsenate. The spraying should begin when the shoots are a 

 few inches high and, when the pest is abundant, should be repeated 

 twice a week. 



Paillot (A.). Les Coccobacilles du Hanneton. Action pathogene sur 

 quelques Chenilles de Macrolepidopteres. [The Coccobacillus of 

 the Cockchafer. Its Pathogenic Action on some Caterpillars of 

 the Macrolepidoptera.] — C. R. Soc. Biol., Paris, Ixxix, no. 20, 

 16th December 1916, pp. 1102-1103. 



Pour different species of Coccobacillus have been isolated during the 

 year from cockroaches in the district round Lyons and in the Jura. 

 These have been classed provisionally as varieties of Bacillus melolontliae. 

 A fifth type, closely allied to B. melolonthae liquifaciens, is however 

 distinguished from it by some culture peculiarities and especially by 

 its action on the rabbit. A series of experiments have been performed 

 with these organisms on cockchafers and on the larvae of Vanessa 

 urticae, Lynmntria dispar and sillcworms. Cockchafers inoculated 

 with B. melolonthae liquifasciens died in 24—36 hours after direct 

 inoculation. After nine passages they died in 10-12 hours. These 

 results are similar to those obtained by Chatton with B. acridiorum 

 [see this Review, Ser. A, i, p. 306]. The other varieties of Coccobacillus 

 gave similar results. The virus obtained after the ninth passage did 

 not cause infection when given by the mouth. Larvae of Vanessa 

 iirticae are very sensitive to the action of these bacilli. Death super- 

 vened in less than 24 hours after direct inoculation and in 10-12 hours 

 after the fourth passage, though virus of this strength does not kill 

 when given through the mouth. Twenty-three successive passages 

 were made with type II. of B. melolonthae liquifasciens ; at the sixth, 

 death supervened in 9-10 hours, at the 20th in 7--9 hours. No higher 

 rate of virulence could be obtained, and this may be taken as the 

 maximum. This virus was also incapable of infecting healthy larvae 

 when given by the mouth. The same strain was used for inoculating 

 larvae of Lymantria, dispar. The first injection was made direct from 

 the blood of the last Vanessa urticae inoculated ; death supervened 

 at the end of 20-24 hours. At the second passage, the rate of virulence 

 had increased considerably and death occurred at the end of 10-12 

 hours. The increase was then slight up to the 23rd passage, when it 

 caused death at the end of 9-10 hours. Silkworms respond to a certain 

 extent to the action of this Coccobacillus. 



Repeated passages through organisms which differ from the original 

 host do not appear to alter the characteristics of these bacilli. 



