356 Tii her cula?' Swellings on Roots of Vicia Faba. [June 1 6, 



that; there is no constant distinction between the so-termed '* dumb " 

 and " furious " rabies. 



4. That the initial virulence of street rabies is usually increased, 

 and becomes remarkably constant, by passmg through a series of 

 rabbits. 



5. That the activity of the virus is shown by the duration of the 

 incubation period, to which it is inversely proportionate. 



6. That the tissues of an infected animal do not themselves become 

 infective till towards the end of the incubation period. 



7. That of a large number of drugs which were tried, both 

 germicides and those acting specifically upon the cerebro-spinal 

 system, none materially modify the action of the virus in the rabbit. 



8. That by a series of subcutaneous inoculations with virus treated 

 by the methods of M. Pasteur, immunity, even against subsequent 

 infection, cannot be conferred upon the rabbit ; and that the extreme 

 and unexpected constitutional refractoriness of the dog to infection 

 with rabies, by any method of inoculation — as I have found ifc in the 

 limited number of experiments I have been able to perform with 

 this animal — renders it extremely difficult to determine the effect of 

 such remedial or prophylactic measures in it ; and that it is by the 

 statistics of the treatment alone that their effect with man can be 

 decided ; but that judging from the results of the experiments of 

 others, the principle of the method as affirmed by M. Pasteur appears 

 to be established, though unquestionably the " rapid " or "intensive " 

 treatment, as I have found, is liable to produce infection. 



III. M On the Tubercular Swellings on tbe Roots of Vicia Faba." 

 By H. Marshall Ward, M.A., F.L.S., Fellow of Christ's 

 College, Cambridge, Professor of Botany in the Forestry 

 School, Royal Indian College, Cooper's Hill. Communi- 

 cated by Prof. M. Foster, Sec. R.S. Received May 29, 

 1887. 



(Abstract.) 



In this paper the author gives a detailed account of his investiga- 

 tions, of which a preliminary note appeared at p. 331. The following 

 are the main conclusions : — 



The tubercles always contain a fungus, allied to the TTstilaginese, 

 which enters the root by way of the root hairs. The ultimate branches 

 of the hyphse in the cells of the tubercle bud off minute bodies (gem- 

 mules), which are afterwards scattered in the soil. This process 

 resembles the budding discovered in Ustilagineae by Brefeld. By 

 means of cultures and observations the author shows that the infec- 

 tion from the soil is probably due to these minute gemmules acting 

 as spores. 



