524 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
fermenting tobacco. Their mode of formation shows that Aspergillus 
fumigatus is the conidial form of a true Eurotium. 
Lachnidium acridiorum.* * * § — M. A. Giard has further investigated the 
life-history of this fungus parasitic on Acridium peregrinum. It occurs 
in two principal forms, a Cladosporium and a Fusisporium form. In 
old cultures there are frequently found clilamydospores, formed at 
first of a single cell, afterwards of two, placed one above the other, 
the terminal one being larger and with thicker walls. The fungus has 
then all the characters of the genus Sarcinella. A parallelism is 
thus established between the different stages of Lachnidium and those 
of Cladosporium ; and it is probable that Lachnidium must be placed 
either in the Perisporiaceae or the Sphseriaceae ; and that the genera 
described as Hormodendron, Sarcinella , Stemphylium, Macrosporium, 
and Mystrosporium, are but stages in the evolution of various Asco- 
mycetes. 
Spotted Anthracnose.t — M. L. Man gin describes the nature of the 
injuries inflicted on the vine by this disease, caused by the attacks of 
Sphaceloma ampelinum. The deformations are essentially due to the 
progressive and complete dissolution of the pectic substances caused 
by the parasite. It also causes an irritation which results in the 
suberification of the layer of cells adjacent to the part attacked, which 
cuts off* the diseased from the healthy part. It is in the buds and 
the young branches that the parasite attains its fullest development. 
Doassansia.:J — Dr. W. A.Setchell gives a further minute description of 
the twelve species of Doassansia which he has already described, together 
with the allied genera Cornuella and Burrillia. 
Oak-cancer.§ — According to Prof. R. Hartig, this disease, which is 
exceedingly destructive to young oaks in Germany, is due to the attacks 
of a parasitic pyrenomycetous fungus Aglaospora teleola , the mycele 
of which penetrates into the wood. Further damage is then often 
caused by Nectria ditissima. 
Dictyonema.|j — M. P. Hariot regards this as a genus of true lichens, 
including as synonyms Dichonema , j Uhipidonema, and Laudatea. The 
fungus belongs to the Hypochnaceae, and probably to the genus Conio - 
phora ; the basids are four-spored ; the alga is a Scytonema. All the 
species hitherto described should be included under one, D. sericeum , 
which occurs in various forms. The thallus is sometimes caespitose 
and but little developed; sometimes silky, spongy, filamentous at the 
margin and reticulate ; when fully developed it is neither reticulate, 
silky, nor spongy. The alga undergoes considerable change in the 
lichenification. 
“ Ginger-beer Plant.” If — Prof. H. Marshall Ward has examined the 
nature of the compound organism which results from the fermenta- 
* Comptes Rendus, cxiii. (1891) pp. 813-6. Cf. this Journal, 1891, p. 636. 
t Loc. cit., cxiv. (1892) pp. 777-80. 
% Ann. of Bot., vi. (1892) pp. 1-48 (2 pis.). Cf. this Journal, 1891, p. 780. 
§ SB. Bot. Yer. Munchen, March 14, 1892. See Bot. Centralbl., 1. (1892) p. 74. 
|| Bull. Soc. Mycol. France, vii. (1891) pp. 32-41. See Bot. Centralbl., 1892, 
Beih., p. 19. 1 Proc. Roy. Soc., 1. (1892) pp. 261-5. 
