ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 471 



Zacharias, O. — Hydrobiologische und Fischereiwirthschaftliche Beobachtungen au 

 einigen seen der Schweiz und Italiens. (Observations on the 

 hydrobiology und fishery economy of certain lakes in Switzer- 

 land and Italy.) Forseh. Ber. Biol. Stat. PIdn, xii. (1905) 



pp. 169-302 (18 BgS.). 



„ „ TTeber die systematische Dnrchforschung der Binnengewasser und 



ihre Beziehung zn den Aufgaben der allgemeinen Wissenohaft 

 vom Leben. (On the systematic investigation of inland waters 

 and their relation to the problems of the general science of 

 life.) Tom. cit., pp. 1-34. 



Fungi. 

 (By A. Lorrain Smith, F.L.S.) 



Chytridiaceae.* — W. Loewenthal describes the species of a new genus 

 Zygorhizidium Willei, which is a parasite of the alga Cylindrocystis. 

 The main part of the fungus remains outside the host tissue into which 

 penetrate short, delicate rhizoids. Besides the usual formation of 

 sporangium and zoospores there is a sexual form of reproduction. Certain 

 individuals — antheridia — form fertilisation tubes which grow towards 

 the female cell, the latter having produced a small protuberance. Fusion 

 takes place, and a zygote is formed. The later history of the zygote was 

 not followed. If no fertilisation occurs the antheridium may become a 

 zoosporangium. 



Monoblepharideae.t — M. Woronin left behind him a series of obser- 

 vations and researches on the genus Monoblepharis, which have since 

 been published. He reviewed first the work done by others on the same 

 subject, and then proceeded to describe more especially M. sphcerica. 

 The chief characteristic of this species is the hypogynous antheridium. 

 He found that frequently the oospheres issue from the oogonium after 

 fertilisation. The development of the antheridia and the process of 

 fertilisation have been carefully followed. He observed that the oogonium 

 was always closed until fertilisation, and that the spermatozoids pierced 

 the oogonial papilla. The wall of the oospore is formed of two layers, 

 and the warts on its surface arise from the inner sheath of the outer 

 membrane. 



Culture Experiments with Morchella.J— Marin MoUiard published 

 some time ago the results of his culture experiments with the spores of 

 Morchella. He at that time succeeded in producing sterile mycelium 

 in pure cultures, and on adding certain organic substances to the medium 

 the conidial form Gostantinella cri&tata grew abundantly. He had 

 noted that Morchella was often found in places where fruits such as 

 apples and pears had been buried, so he planted the sterile mycelium in 

 earth along with apples. In one case Morchella was produced ; in 

 another both Morchella and Gostantinella. Milliard thinks these facts 

 might be utilised in the culture of the Morel. 



* Arch, fur Protisteukunde, v. (1905) pp. 221-39 (2 pis. . 

 f Mem Acad. Imp. Sci. St. Petersburg, ser. 8, xli.. No. 4 (1904) 21 pp.. b pis. 

 Bee also Bot. Centralbl., xcviii. (1905) p. 587. 

 X Comptes Rendus. cxl. (1905) pp. 1 I4f.-S. 



