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sembling that described by her as symptomatic of M. nigrofaciens. I 

 had regarded this as due to the oxidation of the blood or some consti- 

 tuent of the integument. 



With a view to discovering whether the organism occurs as a para- 

 site of the white grub in our soils and also whether Miss Northrup's culture 

 was virulent for our forms it was decided to conduct investigations on the 

 subject. These investigations were handicapped because it was difficult 

 to obtain a sufficient number of larvae from this vicinity. On June 5th. 

 I obtained a white grub which was considerably blackened showing an 

 advanced stage of the disease. It died three days later. Plates were 

 poured and cultures of three different organisms were obtained from the 

 diseased tissues. The most abundant was a putrefactive bacillus, possibly 

 the one Miss Northrup found associated with M. nigrofaciens, and which 

 she regards as Krassilstchik's bacillus of septicemia. A micrococcus 

 resembling nigrofaciens both under the microscope and in plate culture 

 was also isolated. Later on a few white grubs and several larvae of other 

 scarabeidae were obtained. They were put into pots of sterilised soil. 

 Some were sprayed with suspensions of Miss Xorthrup's culture, some 

 with suspensions of the organisms isolated from the first diseased larva, 

 others were left unsprayed as checks. This experiment was inconclusive 

 as in most cases, including the checks, some of the larvae blackened and 

 died while others remained healthy. They were probably infected before 

 being put into the pots. The putrefactive organism was most in evidence, 

 causing the tissues to break down into a disorganised foul smelling mass. 

 In fact in several cases only the brown colour was recognised in the dead 

 integument unaccompanied by the blackening associated with M. nigro- 

 faciens. It will thus be seen that these experiments though incomplete, 

 point towards two conclusions, — (1) that Micrococcus nigrofaciens is pres- 

 ent in our soils, (2) that the putrefactive organism may cause death when 

 not associated with M. nigrofaciens. I do not regard the latter conclusion 

 as definitely proved, however, because it is possible that the putrefactive 

 bacillus attacks the already diseased tissues and it is doubtful whether 

 it is a primary cause of disease. If practicable further work on this subject 

 will be conducted during the coming summer. 



