326 SUMMAEY OF CURRENT RESEARCHES RELATING TO 



has published descriptions of them. The material all came from 

 Porto Rico. The parasitic fungi include one Ascomycete, a number of 

 Pyrenomycetes (more especially Hypocreaceae), some Sphteropsidae, and 

 a varied series of Hyphomycetes. Two new genera are described ; 

 Isthmospora, a genus of Dematiacefe, with two species ; and Grallomyces, 

 with a peculiar dark brown mycelium. No spores or conidiophores of 

 the latter were seen, and it is the only fungus recorded in the paper that 

 is not a parasite ; it is associated with Meliola, but grows on any leaf in 

 suitable conditions. A. L. S. 



South African Perisporiales. — Ethel M. Doidge {Trans. Roy. 

 Soc. S. Africa, 1917, 5, 713-750, 10 pi.) gives a full and systematic 

 account of these fungi as contained in the South African Union Myco- 

 logical Herbarium at Pretoria. There are nine genera, most of them 

 with very few species. Meliola is represented by thirty-two species out 

 of forty-five for the group, and seventeen of the species described are 

 new to science. A host index is supplied, and the paper is well 

 illustrated. A. L. S. 



Development of Cryptomyces Pteridis. — Karl Killian (Zeitschr. 

 Bot., l',)18, 10, 49-126, 31 figs.) presents his elaborate study of this 

 Bracken fungus. He describes the effects produced on the host-plants 

 and the physiological reasons for the rolling up of the leaves under the 

 influence of the parasite. He then gives an account of the fungus itself 

 from spore to spore. The attempt to induce germination of the ascus 

 spores on artificial media failed, but they were found in the very early 

 stages of attack on young Pteris plants ; it was observed that penetration 

 of the hosts by the hyphse occurred only through the stomata. During 

 the summer a conidial form (Sphgeropside^) is freely produced, towards 

 winter the ascus fruit is formed ; the formation and development of 

 this stage are fully described ; copulation between two cells of neigh- 

 bouring hyphse in the ascogonium was observed ; asrial hyph« projected 

 above the surface of the leaf resembling trichogynes, but they were 

 wholly vegetative. The further stages of nuclear fusion and ascus 

 formation are also described. Finally, the author discusses biological 

 and affinity questions. A. L. S. 



Sexuality in Rhizina undulata.— H. M. Fitzpatrick {Bot. Gaz., 

 1918, 65, 201-26, 2 pis.) publishes results of his cytological study 

 of this Ascomycete. Certain hyphte near the centre of the ascocarp 

 became transformed at a very early stage into archicarps. As many as 

 eight archicarps may arise. The hyphse of the archicarp are multi- 

 nucleate, as are the vegetative hyphse, but the nuclei of the former 

 increase greatly by division and the cells become opaque. The terminal 

 cell is small, and, at maturity, shows disorganized protoplasmic contents. 

 It has from analogy been termed a trichogyne, but it does not function 

 as such. As the archicarp matures a pore arises between the cells ; those 

 at the centre produce ascogenous hyphre and the contents of the various 

 cells press into them. The nuclei are paired ; finally crozier formation 

 takes place and fusion occurs in the young ascus. A. L. S. 



