ZOOLOGY AND BOTANY, iMICKOSCOPY, ETC. 405 



Morphology and Biolog-y of Gymnoascus confluens sp. n.* — A. 

 Sartory aiul G. Baiiiier describe the new species as tunning rather large 

 masses of separate plant bodies, each of which consists of a group of asci, 

 surrounded by colourless filaments. These filaments practically dis- 

 appear in the coalescence of the different individuals in the common 

 group. 



The fungus was discovered on dog's dung and on the petals of mar- 

 guerites. The authors found that it grew on almost all the culture 

 media usually employed in the laboratory, and it formed a reddish 

 orange very tenacious pigment, which is soluble in alcohol, ether, 

 benzine, etc. 



Development of Conidiophores in Erysiphacese.f— The method 

 of development is observed and contrasted in several species by M. 

 Bezssonoff. In Sphssrotheca mors-uvse^ the first appearance is a swell- 

 ing in the hyph^e when the nucleus divides twice in succession ; one of 

 the nuclei passes into the swelling which takes a tubular form, a second 

 nucleus from the base also passes in and a septum is formed between the 

 two nuclei of the conidiophore, the basal portion being in open com- 

 munication with the hypha, from which it arose. The upper cell now 

 elongates and a new septum is formed about the middle. These two 

 upper cells by division form four conidia. Other details are added about 

 subsequent division, etc. 



The conidiophores of Microsphsera Ahii also arise by a swelling, into 

 which passes a nucleus from the hypha ; shortly after, a septum cuts off 

 the swelling, which elongates, and then divides, the upper cell dividing 

 again. The lower cell of this second division divides again and becomes. 

 a sort of jDedicel ; the upper cell forms conidia. There are observations 

 on the orientation of the nuclei and the form of the conidia. 



Study in the Development of Xylaria.t — The principal species 

 studied by H. B. Brown w^as Xylaria tentacida^ the " tentacles " being 

 conidial branches that radiate from the end of the fruiting stalk, and 

 which drop off after conidiophores and conidia have matured. 



The perithecia begin as small knots of hyph^e, several layers of cells 

 beneath the surface of the stroma, each knot containing one or more 

 central hyphse, which are shorter and wider than those of the surround- 

 ing hyphge and are rich in protoplasm. These cells lengthen and en- 

 large, forming Woronin hyphse. After a time the cells of the Woronin 

 hyphse separate and form distinct ascogonia, which come to lie in the 

 base of the perithecium as it approaches maturity, and give rise to 

 ascogenous hyphs^e. Each ascogonium contains one nucleus, which 

 divides until some twenty or more are formed. The nuclei in the 

 ascogenous hyphae must also divide, as more asci are finally formed than 

 there are nuclei in the ascogonia. It is thought that the nuclei divide 

 karyokinetically, though division was not seen. 



* BuU. Soc. Mycol. France, xxix. (1913) pp. 261-72 (1 pi.), 

 t Bull. Soc. Mycol. France, xxix. (1913) pp. 279-91 (5 pis.). 

 X Ann. Mycol., xi. (1913) pp. 1-18 (2 pis.). 



Aug, 20th, 1913 2 E 



