ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 79 



Professor Hard's book on fungi is strongly recommended by him as a 

 good popular presentation of a difficult subject. A description is given 

 of the ejection of the peridioles in Sphserobolus and the re-discovery of 

 Bovistslla paludosa is chronicled. Lloyd also gives an account of a 

 new Broomeia, and discusses the differences between Fames applanatus 

 and F, reniformis, an American species. A closely allied species, 

 F. leucophseus, is common in the United States and rare in Europe. 



Freezing of Filamentous Fungi.* — Hugo Bartetzko has carried 

 out a long series of experiments on the subject with a view to studying 

 tlic whole subject of injury to plants by extreme cold. Filamentous 

 fungi, such as Penicillium glaucum, Botrytis cinerea, Fkycomyces nitens, 

 and Aspergillus niger, were chosen for experiment and grown on 

 suitable media. He found that the different fungi reacted differently 

 to cold, that they could all withstand low temperatures but died off if 

 the culture solution was frozen. If the period of cold were prolonged 

 the plants eventually were killed, though this power of resistance was 

 heightened the more concentrated the culture solution. Death by 

 freezing is not simply due to withdrawal of water, because the point of 

 freezing may be at a temperature higher than that at which water is 

 withdrawn in any considerable quantity. The phase of development of 

 the fungus is of considerable importance in the moment of freezing. 



Termites and Fungus-culture.f — K. Escherich contributes a 

 study of the fungus gardens of the white ants. These gardens are 

 (•(instructions of various sizes, and are traversed by gangways in which 

 the fungus is cultivated ; the larva? of the ants are kept in the neigh- 

 bourhood of the fungus and live on it. The fungus itself is clear or 

 dark brown coloured, and forms little pustules, all closely congregate ; 

 tlie substratum on which the fungus grows is of wood, or occasionally 

 of leaves. On the outside of the nests very frequently an Agaric 

 {Volvaria eurhiza) is found, especially after rain. If a portion of a 

 nest is kept under a bell-jar the stomata of a Xylaria make their 

 appearance, so the fungus garden is not a pure culture of Volvaria 

 alone. The latter has never been found apart from termite nests. 



Genera of Fungi. $ — F. E. Clements has compiled, in key form, the 

 genera of fungi, so far as known, taken from Saccardo's Sylloge Fun- 

 gorum, Thaxter's LaboulbeniaceEe, and Zahlbruchner's Lichens in 

 Engler and Prantl's Pflanzenfamilien. He also adds explanations of 

 terms used by Saccardo, list of genera, and a very full index. 



Diseases of Plants.§ — A. D. Selby and T. J. Manns describe a new 

 disease of cereals caused by a fungus, Colletotrichwn cereale sp. n. It 

 attacks the spikes, culms, and sheaths of various grasses ; on cereals the 

 attacks take place as the plant ripens, causing a shrivelling of the grain. 



M. F. Barrus || has studied the dissemination of disease by means 



* Jahrb. wiss. Bot., xlvii. (1909) pp. 57-98. 



t Biol. Centralbl., xxix. (1909) No. 1. See also Centralbl. Bakt., xxiv. (1909) 

 pp. 591-2. \ Minneapolis : H. W. Wilson Co. (1909) 227 pp. 



§ Proc. Ind. Acad. Sci., 1908, p. 111. 

 || Tom. cit., pp. 113-22 (3 pis.). 



