706 The American Naturalist. [August, 
This organism was found, with three exceptions, in 65 
cultures from vaccine points hitherto made. Buttersack whose 
recent investigations will be mentioned in due time ventures 
the supposition that the specific organism of vaccine was not 
hitherto detected, because of its index of refraction being 
identical with that of the medium (lymph). Isee no reason 
for this supposition, and I am prepared to explain Buttersack’s 
theory from my own observations. 
This bacillus has, to a great extent, the same appearance as 
those found by Plaut* and Zimmermann in sheep-pox. 
Already at the beginning of the development, while the 
medium is well stored with nutrition, the bacilli bear spores. 
This being the most conspicuous feature of the organism, I 
named it Dispora variole. The systematic side of the descrip- 
tion is as follows: 
Genus: DISPORA. 
Dispora: Kern, 1882. 
Kern (Botanische Zeitung, 1882, No. 16) founded this genus 
upon one species which was found in kephir and which was 
characteristic mainly by having two spores in each cell. The 
genus belonged to the bacillus-group. Kern’s D. caucasica has 
not been rediscovered by later students of the kephir-organisms 
(Beyerinck, M. Ward, Mix), and the genus-name vanished into 
Bacillus (Crookshank, Manual, 312). 
' Dispora variolæ. 
Syn. The spore stage was described under the following 
names: Microsphæria vaccinæ Cohn, Micrococcus vaccinæ and 
variolæ Cohn, Jos variolosa Salisbury. 
Habitat: In vaccine and small-pox lymph constant. Descer. 
Bacilli 0.6-1.0 » by 0.2-0.3 =. Two spores in each cell, one at 
each end. Aërobic. 
On the sixth days of cultivation, free spores begin to make 
their appearance, both in the fluid and in the zooglœa. They 
are globular, highly refractive, and may be mistaken for what 
appeared to me, by a little over 2000 d. m., as vacuoles. The 
* Loc. cit. Beilage I-IV b; especially II a. 
