92 SUMxMARY OF CURRENT RESEARCHES RELATING TO 



Researches on the Infection of Cereal Rusts.— G. Gassner 

 {Ce?itralbl Bakt., Idlb, AM. 2, 44, 512-617; see also ^nw. 3Iycol, 

 1916, 14, 285-6). The author has worked for several years in Uruguay 

 on rust infection, and he finds that it is in certain cases influenced by 

 the stage of development reached by the host. This is especially the 

 case in Puccinia graminis ; young host plants can resist infection during 

 the greater part of the year, while, at a later stage of growth, the plants 

 are more easily infected and the young leaves of these older plants also 

 suffer. Other results were obtained with P. triticina and P. coronifera. 

 They could infect cereals at any stage up to the time of teleutospore 

 development. The time of maximum infection was found to differ for 

 the various rusts. A warm temperature was favourable to rusts ; the 

 physical condition of the soil had no effect, except through greater or 

 less moisture. A high content of nitrogen in the soil was not found to 

 be particularly favourable to infection. Phosphorous manure had no 

 effect except in the case of P. graminis, when the host plant may 

 have matured earlier and so reached the infection stage more quickly. 



A. L. S. 



Sexuality in the Basidiomycetes. — Mathilde Bensaude {Memoirs^ 

 1918, 1-150, 13 pis., 30 figs. ; see also Mycologia, 1919, 11, 280-3). 

 This is a careful and long study of nuclear phenomena in the mycelia 

 of Basidiomycetes. The writer argues for the sexual significance of 

 the familiar typhal anastomoses in these fungi. Cultured studies were 

 made from spores and from mycelia gathered in the field. In a culture 

 from spores of Coprinus fimetarius she found that mycelium from a 

 single spore grew vegetatively for eight months ; there was no carpo- 

 phore development. With a mixed culture, fruit bodies w^ere formed. 

 She concludes that binucleated cells are formed, following plasmogamy 

 between cells coming from two different thalli, though she also considers 

 that some Basidiomycetes are homothallic, while others are hetero- 

 thallic, as in the Mucorini. Clamp formations and their importance 

 are fully described and discussed. A. L. S. 



Gasteromycetae ZeylanicaB. — T. Fetch {Ann. Roy. Bot. Gard., 

 Peradeniga, 1919, 7, 57-78). Gasteromycetes are very frequent in the 

 tropics and occur under strange forms. T. Fetch has published a list of 

 all those collected in Ceylon by himself or others. He gives an account 

 of the collections and of the various determinations of the fungi. A 

 number of new species are included, and a new genus, Pharus, is based 

 on Lysurus Gardneri Berk. A. L. S. 



Revisions of Ceylon Fungi.— T. Fetch {Ann. Roy. Bot. Gard., 

 Peradeniya, 1919, 7, 1-44). This is part vi. of Fetch's examination 

 of doubtful species ; the numbers treated are 218-72, and comprise 

 some of the larger fungi, though mainly microfungi. There is one new 

 genus, Phseopeltis, based on Micropeltis gomphispora B. & Br. The 

 notes, historical and descriptive, are very full. A. L. S. 



Mycological Contributions.— H. and F. Sydow {Ann. Mycol, 1918, 

 16, 240-8). The paper deals chiefly with a critical examination of 



