ZOOLOGY AND BOTANY, MICROSCOPY* ETC. 
661 
results in the acidification of the wort. To the mechanism of this 
process, or in other words, the explanation of why an acid reaction 
should be favourable to fermentation, Prof. J. Effront has devoted con- 
siderable attention. It has been found that the acid reaction is due to 
the lactic ferment, and acidimetric analysis has shown the optimum per- 
centage to be from 0*9 to 1. Moreover, it is necessary that the leaven 
be not only decidedly acid, but it must have a fresh taste and an agree- 
able odour. After negativing two hypotheses, the peptonisation and the 
antiseptic, the author lays it down that the practical method of yeast- 
making influences the physiological character of the leaven, the cells 
reproduced under these conditions possessing great activity. As, under 
practical and industrial conditions, reproduction is not a marked 
feature, the activity of the leaven is the consequence of the feeble 
reproduction. 
Indian Wheat Rusts.* — Dr. D. D. Cunningham and Mr. D. Prain 
discuss various problems, which cannot yet be regarded as settled, 
respecting the connection of the “ rusts ” which attack the wheat and 
barley crops in different parts of India with one another, and with the 
assumed species Puccinia graminis and P. rubigo-vera. There appears 
to be a distinct connection between them and the parasitic fungus on 
Launea asplenifolia (Composite), a common weed among crops. 
Peridermium and Cronartium.j — Dr. J. Eriksson considers that the 
three forms of Peridermium , P. Cornui , Strobi, and Pini, which occur in 
Sweden, are rather forms of One species, than distinct species, as they are 
usually considered. P. Strobi , parasitic on the Weymouth Pine, is 
undoubtedly connected genetically with Cronartium ribicolum , parasitic 
on Bibes nigrum ; but the latter form appears to be able to propagate 
itself independently from year to year, without the intervention of the 
Peridermium- form ; since it perpetuates itself in districts where there is 
no Pinus Strobus ; and the same is true of C. asclepiadeum in relation to 
P. Cornui. 
Presence of Mould-Fungi in Syphilis, Carcinoma, and Sarcoma. :f — 
Dr. J. Kremer has found in the lesions of syphilis a fungus resembling, 
in many respects a Penicillium. It is very pleomorphic, and in its 
highest development is most like Aspergillus. This SypJiilis-aspergillus 
is possessed of a mycele on which appear fruit-hyphae, both aerial and 
submerged. Its polymorphism is exhibited by transition forms resem- 
bling Oidium, Dematium, and Botrytis. This fungus has been cultivated 
from seven cases of syphilis, from cases of Carcinoma linguae and Melano- 
Sarcoma of the skin. Aspergilli were also obtained ; in both instances 
the fungi presented considerable likeness to the Aspergillus of syphilis,, 
but were distinguished therefrom by some well-marked differences. 
The microscopical appearances are depicted and described from fresh 
preparations only. 
Development of Mutinus.§ — From a study of the development of 
Mutinus caninus, Dr. E. A. Burt comes to the conclusion that the two 
* Kecords of the Bot. Survey of India, i. No. 7, ] p. 90-124, Calcutta. Cf. this 
Journal, 1892, p. 402. 
t Centralbl. f. Bakteriol. u. Parasitenk., 2 te Abt., ii. (189G) pp. 377-94. 
1 Op. cit , l te Abt., xx. (1896) pp. G3-85 (15 figs.). 
§ Ann. Bot., x. (1896) pp. 343-72 (2 pis.). 
1895 2 z 
