H. Dold 
285 
shaven skin. No pathogenic effect followed. The shaven part of the 
skin again became covered with hair. The skin and hair both remained 
normal. 
The two guinea-pigs were each inoculated intraperitoneally with 
0 - 5 c.c. of a two days’ broth culture. The animals showed a transitory 
indisposition, but soon recovered, and remained healthy for four months 
(present date). 
Two rabbits were injected subcutaneously in the back, with On c.c. 
and TO c.c. respectively, of a three days’ culture of the organism. No 
suppuration resulted. The organisms were evidently destroyed and 
absorbed. The animals remained healthy for four months (present 
date). 
Two other rabbits received respectively 05 and TO c.c. of a three 
days’broth culture injected into the ear-vein. After a period of uneasi¬ 
ness, lasting one to two days, the animals recovered and seemed healthy. 
They were killed three months after the inoculation. The organs were 
normal, excepting one suprarenal gland ; this was enlarged, and was 
found on microscopic sections to contain suppurating foci, in which 
numerous D. M. (spheroid, ovoid, bacillary and bottle forms) were 
present. 
From these experiments it is evident that the D. M. is not 
pathogenic for rats and guinea-pigs. The slight effect observed in one 
rabbit, after the intravenous injection of a large dose of culture, is 
curious, but cannot be accepted as sufficient evidence that the organism 
is really pathogenic. The experiments on animals do not of course 
exclude its being pathogenic to man, though this appears rather 
unlikely; I regret that I had no opportunity of testing this experi¬ 
mentally. 
Malassez distinguishes three types of this organism, the distinction 
being based on the size of the individual cells. Having shown the 
extraordinary polymorphism, of which D. M. is capable, I think that 
this distinction is not justified. The same is true of his distinction 
between the “ champignon de la pelade ” and the “ champignon de la 
pityriasis simple ” and of his assumption that the ovoid forms to be met 
with belong to another species. The mere morphological differences, 
which led Malassez to regard these forms as distinct, also appear to me 
to be insufficient. It is possible that the organisms found in Pityriasis 
differ biologically from those found on healthy or seborrhoic skins 
(like those from which I obtained my cultures), but it is most im¬ 
probable. 
