ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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those in which the mycele hibernates within the tissues of the host- 
plant. It does not appear to occur in other genera of Uredinese than 
these two. 
Fungus intermediate between Ascomycetes and Basidiomycetes.* 
— According to M. R. Ferry, the sclerote-fungus known as Mylitta 
australis is not only connected with the basidiomycetous form Polyporus 
Mylittse , but produces also in its interior an ascogenous layer. 
Protophyta. 
/3. Scliizomycetes. 
Structure of Bacterial Cells.j — In a preliminary communication 
Mr. H. Wager lays it down that in a bacterial cell there are two different 
substances to be recognised— a nuclear substance and a cytoplasmic 
substance ; that the nuclear substance has a definite structure which is 
found in principle in all bacterial cells, and which plays an important 
part in the division of the cell ; but that it is simpler in form and struc- 
ture than the nucleus of the higher plants and animals. The author’s 
observations were made on Spirillum undula and on a bacillus with a 
gelatinous capsule. 
Variations in the Biological Characters of Bacteria.^ — Mr. H. G. 
Dyar made observations on two kinds of bacteria for the purpose of 
ascertaining to what extent variations in biological characters became 
evident in ordinary cultivation media. . * 
(1) Merismopedia rosea (syn. Micrococcus roseus ; Sarcina rosea'). 
Five samples of different origin were used. Gelatin was liquefied in 
from 10-50 days. There was no coagulating effect on milk. All the 
samples grown in nitrate solution effected a moderate reduction to 
nitrite. On potato only one sample grew well. With regard to colour 
there was practically no difference, all the growths being pink. 
(2) Bacillus lactis erythrogenes (syn. B. versicolor , B. helvolus ). 
Seven samples from different sources were employed. Liquefaction of 
ihe gelatin usually began on the third day, but was sometimes deferred 
till much later : the degree of acidity of the medium was noticed to have 
a distinct effect on the rapidity of the liquefaction. The casein of 
milk was slowly precipitated and peptonised, the reaction of the medium 
becoming neutral or alkaline ; the clot, however, was never distinct, 
even after boiling. Nitrates were usually quickly and thoroughly 
reduced to nitrites. The colour of the growths was yellow, that of the 
medium being pink. 
Bacterial Variation^ — Prof. H. M. Ward is of opinion that it is 
extremely probable that (1) variations in the form, rate of growth, size 
and colour, and other characters of plate colonies result from much 
slighter variations in the gelatin and other environment than has 
hitherto been recognised. (2) That, regarding the water of a river as 
a food medium, the vicissitudes which a Bacillus has been exposed to 
in this medium, previous to its capture and isolation in the laboratory, 
* Rev. Mycol., 1895, p. 162. See Hedwigia, xxxiv. (1895) Rep., p. 176. 
t Ann. Bot., ix. (1895) pp. 659-61. 
X Trans. N. Y. Acad. Sci., xiv. (1895) pp. 94-9. 
§ Ann. Bot., ix. (1895) pp. 653-7. 
