ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 687 



vatiug the parasites, with an account of inoculation experiments em- 

 ployed to verify the identity of the fungus with the origin of the disease. 

 The fungi are all minute species. In the group of Phycomycetes he 

 describes several forms of the Mucorincae. Among the pathogenic Asco- 

 mycetes he includes forms of Saccharomycetinese and Plectascineae, and 

 under Fungi imperfecti he describes the diseases due to Discomyces, 

 Oidium, &c. 



Fungal Disease in Horses.* — J. de Haan has investigated a disease 

 of horses in Batavia. He found that it was caused by the presence of a 

 fungus in the skin, more especially in the mucous membrane of the 

 mouth, lip, and nose. In the later stages the bones of the head are 

 also attacked. An examination showed the presence of yellowish-grey 

 lumps of a somewhat hard formation varying in size from the head of 

 a pin to an egg ; and traversed in all directions by a well-developed 

 mycelium which also penetrated the surrounding tissue. The writer 

 has named the fungus Hypliomyeosis destruens equi, and he is of opinion 

 that it is the sole origin of the malady. Infection comes from the food, 

 and the fungus gains entrance to the tissue through some small wound 

 in the mucous membrane caused by the grasses, &c. that compose the 

 fodder. In the external skin the fungus would similarly find entrance 

 through some abrasion. De Haan made cultures of the fungus, and with 

 these he re-infected the mouth and neck of healthy horses. The experi- 

 ment was unsuccessful. 



Continuity of Protoplasm in Fungi.j — Arthur Meyer reviews 

 the work already done on this subject by (Jbmielewsky, Wahrlich, and 

 others, and gives an account of the different fungi in which this phe- 

 nomenon had already been noted. He devotes special attention to the 

 mode in which the perforating protoplasmic strands are formed between 

 the cells. There are two possible ways in which this could take place : 

 that the closed membrane should be pierced by the protoplasmic strand, 

 or that the opening should be left in the wall at its original formation. 

 He finds that the latter is the process followed in the fungi. Meyer 

 discusses also the fusion of kyphae and the occurrence of clamp con- 

 nections with reference to the subject of continuity between cells. 

 Fusion of hyphaa has been demonstrated by various observers in many 

 Basidiomycetes and Ascomycetes, and in the promycelial cells of the 

 Ustilagiuea). It has been noted in the germinating tube of the uredo- 

 spores of Uromyces Pose, but not as yet in any other member of the 

 Uredineae. The author discusses at some length the bearing of these 

 facts on the phylogeny of the group. The paper is followed by a large 

 and complete bibliography of the subject. 



Influence of Light on the Respiration of the Lower Fungi.J — 

 N. A. Maxiinow gives the results of his researches on two species of fungi, 

 Mucor stolonifer and Aspergillus niger. He used direct sunlight or the 

 light from an electric lamp for the illumination of the plants, and he 

 grew them on various media. He found that the influence of the light 

 varied Avith the age of the cultures : at a young stage light had no effect 



* Centralis. Bakt., 1" Abt., xxxi. (1902) pp. 758-63 (2 figs.). 



t Bot. Zeit., lx. (1902) pp. 139-78 (I pi.). 



J Centralbl. Bakt., ix. (1902) pp. 193-205 and 261-73. 



