118 PKOTISTS AND DISEASE 



is fully illustrated, and shows, in the authors' opinion, that 

 the lesions obtained were developed in connection with 

 hair-follicles and sebaceous glands. The authors believe 

 that the lesions are recognisable clinically before the mol- 

 luscum bodies develop, and conclude therefrom that the 

 bodies are degeneration-products. Their results confirm 

 previous findings to the effect that the virus of Molluscum 

 Contagiosum is filtrable. 



The Identity of Plassomyxa Contagiosa with the Filtered 

 Virus. When one examines in sections a fully-developed 

 tumour, e.g. Plate III, Part IV, it is seen that the proportion 

 of parasites to host-tissue is very considerable. Roughly, 

 one-third of the weight of the tumour must consist of the 

 parasites, and a casual relationship of the latter to the 

 disease is thus seen to be more than probable. 



Again, it is certain that parasites which cause the disease 

 are contained in the filtrate of experiments, such as that of 

 Wile and Kingery. 



There is no inconsistency in the two groups of facts. 

 After the use of the pestle and mortar biological units, 

 capable of being drawn by suction through the pores of the 

 filter, are free in the liquid medium. Such units, I do not 

 doubt, are a plasson phase of Plassomyxa contagiosa. 



Synchytrium and Plassomyxa contagiosa compared. 

 Comparable features in synchytrians and the causal parasite 

 of molluscum are found in the nucleolus of the former and 

 the whole body of the latter. Invisible in its earliest stage 



