ZOOLOGY AND BOTANY, MICROSCOPY, ETC. -"'45 



herhacea be found a new species of Olpidium, and traced the development 

 — first a naked cell with nucleus which might become a zoosporangium 

 or two cells might fuse (indicating sexuality) and a resting spore be 

 formed. Nemec also describes the process of infection. 



Conidiophores of Erysiphaceae.* — M. Foex has made a comparative 

 study of the different species of mildew, and has found considerable varia- 

 tion in the form of the conidiophores. He recognizes four distinct types : 

 1. The basal cell directly produces the conidia. 2. There is a unicellular 

 pedicel supporting the mother-cell of the conidia. o. A very slender 

 pedicel often pluricellular. 4. Also a slender pluricellular pedicel on 

 which is borne the fertile cell, or the pedicel may branch and so give 

 rise to more chains of conidia. 



Notes on Oak Mildew.f — E. Noffray reports that in 1911 the attack 

 of the oak mildew was less severe than in previous years. As a rule oaks 

 of more than five rears of age were immune. The writer thinks if there 

 were no felling of oaks for some years the disease would gradually 

 disappear, as young shoots are peculiarly liable to attack. 



New Yeasts. — The new genus Guilliermondia was found by (i. A. 

 Nadson | and A. G. Konokotiue in the slime-flux of the oak, along with 

 some other fungi. The cells are ovate, ellipsoid, or lentiform. The ascus 

 arises from the heterogamous copulation of two cells, two gametes, a 

 large female cell and a smaller male cell. The copulation product forms 

 a new large cell into which the contents of both gametes pass, and it 

 becomes the ascus with one or rarely two globose spores. The spore 

 membrane is brown with minute warts. As the name GuiUiermondia is 

 already occupied, the reviewer in Ann. Mycol. (H. Sydow) suggests the 

 name Nadsonia. 



A. A. V. Richter§ gives an account of a yeast Zygosaccharomycp.s 

 melUs-acidi sp. n. that sets up a fermentation in honey. The yeast-cells 

 are very small and therefore able to live and increase in such a concen- 

 trated solution as honey. 



Green Forms of Penicillium. |1 — Richard Westling has made an 

 exhaustive study of this group of moulds. He has made cultures of 

 the different species on various substrata, and has found that the spores 

 are the most reliable diagnostic character, as they remain unchanged in 

 the diflferent culture conditions. The species were obtained from decaying 

 fruits, cheese, etc. He found that Goremiiim formation was not induced 

 by nutritive conditions, but that it was a character peculiar to certain 

 species, and therefore of considerable diagnostic value. Westling inclutiL'S 

 Citromyces in PeniciUiuni. 



* Rev. G6n. Bot., xxiv. (1912) pp. 200-6 (4 figs.). 



t Journ. Agric. prat., Paris, i. No. 14 (1912) pp. 432-3. See also Bull. Bur. 

 Agric. Intell., iii. (1912) pp. 1232-3. 



X Bull. Jard. Imp. Bot. St. P6tersbourg, xi. (1911) pp. 117-43 (45 figs.). See 

 also Ann. Mycol., x. (1912) pp. 347-8. 



§ Mycol. Centralbl.,i. (1912) pp. 67-76 (4 figs.). 



II Ark. Bot., xi. No. 1 (1911) 156 pp. (81 figs.). 



