214 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Eriksson * writes on the significance of the Barberry in the propaga- 

 tion of wheat rust. There are seven different biological forms of Puccinia 

 graminis in which the aacidium is to be found on the Barberry, but the 

 gecidiospores will only reinfect the grass from which it originated in the 

 first instance— all other crops are safe from that particular rust. Eriks- 

 son notes also that aecidiospores from the Barberry do not germinate 

 easily, and he concludes from his study of the subject that it is quite 

 safe to cultivate the Barberry, as it plays a comparatively small part in 

 rust propagation. 



J. 0. Arthur f publishes the results of his series of culture experiments 

 for 1907. In the first 17 recorded, no results were obtained. A second 

 list of 22 includes those species which had been already experimented 

 with, but in which additional knowledge was gained as to germination, 

 etc. He records further H species of Uredinese that were successfully 

 cultivated for the first time. 



W. Miiller % has undertaken an exhaustive study of Melampsora on 

 Euphorbiacefe. He has established 7 biological species in M. helioscopice. 

 There is one that grows on Euphorbia helioscopia alone, the other forms 

 are confined to different species of Euphorbia. The author has also 

 made observations on the time of teleutospore germination, the duration 

 of the period of incubation, etc. 



Walther Krieg § publishes the results of an extended series of similar- 

 experiments with the Uromyces that form their aecidia on species of 

 Ranunculus. He has established some new biological species, and fixed 

 the limits of growth of the many forms dealt with. 



Sphaceolotheca on Polygonum. |] — De Bary separated this genus 

 from Ustilayo because the hyphaj were not entirely converted into spores 

 as in the latter genus. Four species are now known : Sph. Hydropipieris 

 on Polygonum Hydropiper ; Sph. borealis on P. Bistortm ; and Sph. 

 Polygoni-vivipari, which were included by De Bary under the first- 

 mentioned. H. C. Schellenberg in the paper before us describes the 

 appearance and development of all of these, and gives the reasons for 

 separating them. The fourth species, Sph. alpina sp. n., on P. alpinum, 

 is also carefully described ; in it, the spore layer is found between the 

 leaf-sheaths and the flower-stalks, and infection 7 probably takes place 

 during the development of the flower. The so-called columella of this 

 fungus is composed of sterile hyphse that surround the vascular bundle 

 of the host ; similar hyphae clothe the wall of the attached capsules. 



Growth of Woody Fungi. H — L. Mangin has made observations on 

 the growth of some of the larger Polyporeae. He calculated that a large 

 fructification of Unyulina fomentaria measuring 3*50 m. in circum- 

 ference and 20 cm. thick, had grown entirely in not more than 11 

 months. Similar observations had been made on U. betulina, of which 

 the growth is similarly rapid ; a few months only are necessary for the 

 growth of woody fungi 40 cm. and more in width. 



* Illustr. Landw. Zeit., No. 41 (1907). See also Centralbl. Bakt., xx. (1907) 

 pp. 188-9. t Jouru. Mycol. xiv. (1908) pp. 7-26. 



J Centralbl. Bakt., xix. (1907) pp. 441-60. 

 § Tom. cit., pp. 697-714 and 771-88. 

 || Ann. Mycol., v. (1907) pp. 385-95 (1 pi.). 

 1 Bull. Soc. Mycol. France, xxiii. (1907) pp. 155-6 (1 pi.). 



