ZOOLOGY AND BOTANY, MICEOSCOPY, ETC. 75 



on the stigma, the hyphas penetrate to the developing ovule, and remain 

 there until the following season. When the seed is sown, the fungus 

 develops along with the host-plant, and becomes first visible as smutted 

 heads of wheat or barley after the time of blooming. The smut spores 

 of oats are much more resistant, and retain their vitality for some years. 

 The method of infection is also quite different ; the spores germinate on 

 some saprophytic substance, manure of some kind, and directly infect 

 the young plants. The spores of these plants are, like the pollen of 

 their hosts, wind-borne. The smut spores of the maize also develop 

 as saprophytes, and produce conidia, which are carried by the wind to 

 the host plant ; they alight on the young and tender portions of the 

 plants and penetrate into the tissues. The disease appears on the area 

 infected by the spores. Brefeld includes in his survey the smut of 

 Melandrysum, which appears in the anthers, and the smut of water 

 plants such as Phragmites. The spores of the former are carried, as the 

 pollen is carried, by butterflies. In plants like Phragmites the water 

 conveys the spores to new hosts. 



The author concludes with a consideration of the part played by 

 filamentous fungi in the assimilation of free nitrogen. He is of opinion 

 that such assimilation is confined to the Rhizobise of the Leguminosae. 



Genus Phragmidium. II.* — P. Dietel has followed up a previous 

 paper on this genus by a still more extended study of species. The 

 material used was from herbaria in Berlin, Leipzig, and Paris. He calls 

 attention to the uredo form and to the paraphyses which often vary a 

 good deal and are of service in determining species otherwise very much 

 alike. The diagnoses and descriptions of a number of new species are 

 given. A list of the species recognised as such by the author is given 

 with their host-plants. There are 16 on species of Rubus, 15 on Rosa, 

 10 on Potentilla, one of which grows also on Fragaria, the remaining 

 5 are parasites of Geum, Ivesia, Poterium, and Sanguisorba. 



Asparagus and Asparagus Rusts in California.! — Ralph E. Smith 

 has published an account of this Uredine, giving a history of the disease, 

 a description of the various spore forms of the fungus, and an account of 

 the spraying experiments. Dew is essential to the germination of the 

 spores, and dusting with fine sulphur while dew is on the plants has been 

 found to be effective in checking the spread of the fungus. After 

 September the rust is kept down by the parasites Darluca filum, Tuber- 

 cularia persicina, and Cladosporium sp. The latter is a new record. 



New Genus of Uredineae : Uromycladium.J — The rust found 

 hitherto on species of acacia belong to the two genera Uromyces and 

 Ravenelia. D. McAlpine records a new genus which occurs on 

 Australian acacias. The teleutospores of Uromycladiwn are borne at 

 the tips of a branching sporophore, each branchlet bearing one to three 

 spores with a colourless vesicle or cyst below the spores. With the 



* Hedwigia, xliv. (1905) pp. 330-46. 



f Bull. California Agric. Exper. Stat., clxv. (1905) pp. 1-100. See also Bot. 

 Centralbl., xcix. (1905) p. 513. 



+ Ann. Mycol., iii. (1905) pp. 303-23 (4 pis. and 5 figs, in text). 



