350 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Urophlyctis Alfalfa?.* — Korff has written an account of this fungus, 

 which lives on the roots of Alfalfa, and forms outgrowths very similar 

 to those caused by Chry&ophlyctis endobiotica on potatoes, and reaching 

 the dimensions of a nut or of a fist. 1' rapid yet is is one of the Chytri- 

 dinea3, and was first described by Magnus. It does not seem to harm 

 the Alfalfa, as the plants with swellings on their roots were always the 

 biggest and healthiest-looking. 



Development of Helvella elastica.f — W. A. McCubbin gives a 

 sketch of work done on the group of liiscomycetes to which Helvella 

 belongs, and then describes his own material and methods. The 

 mycelium of the fungus is subterranean ; the young stages were taken 

 from a bank of loose damp sand in High Park, Toronto. The author 

 found in the mycelial tissues certain large irregular cells, which were 

 apparently storage-cells. The ascogenous hypha? arise as a subhymenial 

 complex of filaments, and from this layer arise vertical hyphre.of which the 

 end cells contain two nuclei. Hooks are formed by these end cells, the 

 penultimate cell being two-nucleate, and either forming the ascus or 

 giving rise to a second hook (as many as six hooks may thus arise from 

 successive penultimate hooked cells). The terminal and antepenultimate 

 cells are uninucleate, but often they fuse and give rise to a filament 

 which also forms a hook. No structure having the conventional form 

 of an ascogonium was found. 



y to v 



Systematic Position of Urnula Geaster.ij: — This species was named 

 and described by Peck from dried material. F. D. Heald and F. A. Wolf 

 have recently secured living specimens that enabled Peck to supplement 

 and complete his previous diagnosis. It had, meanwhile, been made 

 the type of a new genus, Choriactis, on account of the supposed paren- 

 chymatous wall of the apothecium. The authors show that the wall is 

 made up of interlaced hyphte with large intercellular spaces, and the 

 species is a true Urnula. 



Xylaria Hypoxylon. § — E. Harder has studied the relation of 

 Xylaria Hypoxylon to the wood on which it grows. He grew it on pine 

 cultures, and gives his observations. Xylaria hyphre never impart a 

 dark colour to the wood : it is either white or clear brown ; the dark 

 colour so often present is due to some other fungus. The Xylaria 

 hyphre, which may be parasitic, are colourless, thin, and full of plasma 

 at the early stages ; later, they become thick-walled and empty. A 

 second form of mycelium, which is brown coloured, may be considered 

 a kind of resting form. Xylaria mycelium can resist drought, but for 

 good development great humidity is necessary. Beech-wood is the best 

 substratum for the fungus ; pine-wood the least advantageous. 



American Hypocreales iii.|| — F. J. Seaver continues his monograph 

 of this group. He divides Hypocreacete into two families, Hypocreae 



* Prakt. Bl. Pflanzensch. Pflanzenb., vii., No. 12 (1909). See also Centralbl. 

 Bakt., xxvi. (1910) pp. 563-4. 



t Bot. Gaz.,xlix. (1910) pp. 195-206 (3 pis.). 



X Tom. cit., pp. 182-8 (1 pi. and 3 figs.). 



§ Oesterr. Bot. Zeitschr., lix. (1909) pp. 275-9, 299-302. See also Bot. Centralbl., 

 cxiii. (1910) pp. 172-3. 



|| Mycologia, ii. (1910) pp. 48-92 (2 pis.). 



