ECONOMIC ZOOLOGY ENTOMOLOGY. 251 



ing, and symptomatic anthrax bacilli, etc., and the trn^anosomes of nagana 

 and dourine, they succumb to the glanders and mouse typhoid bacilli and to 

 certain nonpathogenic species, such as the hay bacillus (B. suMilis), when 

 these are injected into the body cavity. Caterpillars infected with the fish 

 tubercle bacilli died within 2 or 3 days after inoculation. 



During the last 2 years the author has from time to time observed diseased 

 caterpillars and in 2 instances epizootics that destroyed nearly all the cater- 

 pillars that were being bred for experimental purposes. In searching for the 

 causative agent of these epizootics, 2 associated micro-organisms were met with, 

 one a motile rod, the other a coccus. Both grew well in bouillon and gelatin 

 and round white colonies wei-e formed on solid media. The rod form was the 

 more virulent, caterpillars injected with small quantities of it succumbing in 

 from 2 to 4 hours when kept at 37° C. Inoculations of the coccus caused their 

 death in from 15 to 20 hours. Neither the placing of healthy caterpillars with 

 those suffering from the disease nor the feeding of cultures of the 2 organisms 

 mixed with small pieces of beeswax produced the disease. Thus the manner 

 in which infection takes place in nature was not determined. 



The reduction of domestic mosquitoes, E. H. Ross (London, 1911, pp. X-{- 

 lUu pJ>i. 13, figs. 2; rev. in Science, n. ser., 34 {1911), No. 885, pp. 8//2--S-/// ) .— 

 This book furnishes instructions for the use of municipalities, town councils, 

 health officers, sanitary inspectors, and residents in warm climates. 



On the varieties of Bacillus coli associated with the house fly (Musca 

 domestica), W. Nicoll {Jour. Hyg. [Cambridge], 11 {1911), No. 3, pp. 381- 

 889). — "A study of the natural bacterial flora of the house fly appears to be 

 essential in forming a correct estimate of the part played by flies in trans- 

 mitting pathogenic bacteria. The house fly may carry at least 27 varieties of 

 B. coli, by far the most frequent of which are B. coli communis and MacConkey's 

 bacillus No. 71. As far as can be judged from the character of these colon 

 bacilli the house fly derives its bacterial flora equally from excremental matter 

 and from other sources. Certain nonlactose fermenting bacilli appear to be 

 capable of multiplying in the intestine of the house fly. Of these Morgan's 

 bacillus No. 1 is a not infrequent inhabitant of the fly's intestine and B. para- 

 typhosus B has been found on 2 occasions." 



On the survival of specific micro-organisms in pupae and imagines of 

 Musca domestica raised from experimentally infected larvae. Experiments 

 with Bacillus typhosus, J. C. G. Ledingham {Jour. Hyg. [Cambridge], 11 

 {1911), No. 3, pp. 353-5 JO). —"Although typhoid bacilli were liberally supplied 

 to larvje of M. domestica, all attempts to demonstrate B. typhosus in the pupse 

 or imagines were unsuccessful, until recourse was had to disinfection of tlie 

 ova. After this preliminary disinfection both larvae and pupae gave pure 

 growths of B. typhosus but hitherto it has not been possible to examine the 

 imagines. . . . 



" From the practical point of view the main conclusion to be drawn from 

 the experiments detailed in this communication is that the typhoid bacillus can 

 lead only a very precarious existence in the interior of larvie or pupae which 

 possess, at least in so far as these investigations warrant, a well-defined bac- 

 terial flora of their own. Even under the highly artificial conditions of the 

 final series of experiments, it was not possible to decide whether the B. typhosus 

 though recoverable from the pupa was really actively multiplying in the pupal 

 interior or gradually dying out. There was some indication that the latter 

 was the case, as the typhoid colonies recovered from the pupa in the one suc- 

 cessful instance were extremely few in number, while the larvae which had 

 been feeding on B. typhosus contained enormous numbers as evidenced both 

 by cultural and microscopical examination," 



