ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 91 



finds that the position of the uredospores depends on the stomata, and 

 they are mostly to be found only on the side of the leaf where they are- 

 formed. In certain cases, however, where stomata occur on both 

 surfaces, the uredospores are confined to one. Teleutospores appear 

 very often on the side of the leaf free from stomata. A. L. S. 



Some New Roumanian Uredinese. — J. C. Constantineanu {Ann^ 

 Mycol., 1916, 14, 268-536, 6 figs.). The author here describes five 

 new species belonging to JJromyces and Puccinia. Very full descrip- 

 tions are given, with figures of the various spores. Comparisons are 

 made between the species described and allied forms. A. L. S. 



Grass Rusts of Unusual Structure. — J. C. Arthur and E. B. 

 Mains {Bull Torrey Bot. Club, 1919, 46, 411-5, 2 figs.). The 

 authors remark on the close resemblance of the leaves of Olyra 

 (PaniceaB) with those of various bamboos. This has led to some confusion 

 in determining the hosts of their respective rusts, but also there is a 

 curious resemblance between these rusts. Comparisons are drawn 

 between three of them : — Puccinia pallescens on Tripsacum, P. phaJcsop- 

 soroides sp. n. on Olyra, and Uredo ignava on the genus Bambusa. 

 Tropical rusts frequently produce thin-walled, pale or colourless spores^ 

 with a fringe of incurved hyphoid paraphyses. The authors find these 

 characters present in the species examined. A. L. S. 



Systematic Position of Uredo alpestris Schrot. — P. Dietel {A7in, 

 Mycol., 1916, 14, 98-9). This Uredo on Viola Uflora is frequently 

 found in the Alps. There occur in the sori spores of two kinds : broadly 

 fusiform with a projection at the apex, or ellipsoid and without any 

 projection. Dietel holds that such uredospores are only known in the 

 genus Uredinopsis. In other respects also the Uredo is similar to that^ 

 of the above genus. A. L. S. 



Research on the Behaviour of the Nuclei in the Reproduction, 

 of Smut Fungi. — Eugen Paravicini {Ann. Mycol., 1917, 15, 57-96,, 

 6 pis., 5 figs.). The author gives an historical account of work done on 

 the reproductive nuclei of fungi. He then sets out the problems still 

 awaiting solution in the Ustilagineae, and describes the methods he 

 employed in his research. He wished to verify the nuclear fusions 

 already described in Ustilagineae and Tilletiae ; to examine further species- 

 as to whether in the copulation of conidia and promycelia there was a 

 passing over of protoplasm along with the nuclei, etc. The solution of 

 these and other problems was sought in the germination of spores in 

 artificial cultures of many species. He confirmed the presence of one 

 nucleus in the spore, which divides or germinates, one of the daughter- 

 nuclei passing to the promycelium. The conidia formed on the promy- 

 celium are also uninucleate. When two conidia copulate the nucleus 

 and protoplasm of one cell pass to the other. Mycelial cells copulate 

 similarly. A binucleate coujugate condition thus arises and is to be 

 found in the mycelium of infected host plants. Fusion between the 

 conjugate nuclei takes place on spore-formation, and this the author 

 regards as a sexual act. A. L. S. 



