Xo. 323] 



NOTES AND LITERATURE 



r>9 



is more than equivocal and that the vitiation is of reasoning not 

 of inheritance. 



So far as I know, only one other investigator besides Russo 

 has laid claim to having modified the ordinary course of Men- 

 delian inheritance by external conditions. Such a claim, if I 

 rightly understood him, was made by Professor W. L. Tower, in 

 a paper read at the last annual meeting of the American Society 

 of Naturalists, in the case of beetles of the genus Leptinotarsa. 

 Detailed information regarding the cases in question will be 

 awaited with much interest. It is to be hoped that this will 

 prove more complete and satisfactory than Russo 's. 



W. E. Castle. 



Harvard University, 

 June 11, 1910. 



THE BUBONIC PLAGUE 

 Bubonic plague is primarily an animal disease. Its original 

 victim is said to have been a species of rodents found in the 

 mountains of Mongolia. Several Russian scientists have sought 

 to establish this hypothesis, according to which the Arctomys 

 lobar, a Mongolian marmot, is the primitive animal host. In it 

 the disease is permanently prevalent, and from it both man and 

 the rat are infected periodically. According to the view of 

 these writers the filial eradication of the plague from our globe 

 would be accomplished by the extermination of this rodent. 

 That this view is over-optimistic may be inferred from the prob- 

 able existence of other ancient centers from which plague epi- 

 demics have originated, and in which, consequently, permanently 

 infected animals are at home, and also from the recent origin of 

 such an established center of animal infection on our own con- 

 tinent. 



In the introduction to an article on Plague Eradication Meas- 

 ures (Squirrel Campaign) in California, Rucker 1 comments on 

 the epizootic which for four years has been spreading among the 



cently has been reported from other districts also. The animal 

 infected is Cifdlus bccvJuiji. which is reported by ranchers to 

 have died by the thousands in l!H>U ,"> -(>. In appearance and 

 habits, it resembles closely the Thibetan marmot referred to 



plague-infected squirrels was the disease of the latter subject 



