ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 423 



emission of the zoospores, which usually takes place at the close of a 

 bright sunny day. It is only in the case of terrestrial species, such as 

 some species of Synchytrium, that the emission is favoured by moisture. 

 Temperature appears to have some influence on their development, but 

 its effect is not general. 



The author divides the family into two groups, one consisting of the 

 genera destitute of mycele, the other having nutritive filaments, even if 

 rudimentary. The members of the former group are necessarily parasites 

 within the cells of the host ; and it is again divided into two sections, 

 according as the sporange is simple or compound. In the second group 

 the position of both mycele and sporange in relation to the host vary ; 

 in some the sporange only is exposed ; in others it is only the ex- 

 tremities of the mycele which penetrate the cells of the host ; other 

 species again are entirely endogenous. 



Eosen's section Dentigera of Chytridium is referred by the author to 

 the genus Bhizidium. The following new species are described : — - 

 Group I. Section 1, Olpidium Sphseritse ; Group I. Section 2, Micromyces 

 Zygonii ; Group II. Chytridium Braunii, C. zoophtJiorum, C. Brebissonii, 

 C. simplex, G. Elodeae, and Bhizidium catenatum. 



Rhamphospora, a new genus of Ustilaginese.* — Dr. D. D. 

 Cunningham describes, under the name Bhamphospora Ntjmphaeae, a 

 fungus parasitic on the leaves of several species of Nymphsea in India. 

 The spores are produced singly, near the sporiferous branches but not 

 actually at their extremities, and are beaked when mature. The 

 promycele consists of a long germinating tube, with terminal branches 

 which bear the sporids at their apex. The sporids of one branch 

 conjugate with those of another. 



Fungi parasitic on the lower Animals and Plants.f— Herr W, 

 Zopf describes in detail a number of fungi parasitic on nematode worms, 

 desmids, diatoms, and other low organisms, animal and vegetable. 



Arthrcbotrys oligospora is a fungus carrying on at first a saprophytic 

 existence on damp wood or soil, decaying fruit, excrements, &c. Its 

 branches present the peculiarity of bending, so as to form loops in 

 which species of Anguillula get captured, and are then rapidly attacked 

 and destroyed by the mycele of the fungus. The author observes that 

 the result of the attacks of the parasite is to set up a fatty degeneration 

 in the organs of the animal attacked. In addition to the ordinary conids, 

 Arthrobotrys produces resting-spores. 



Another very minute fungus parasitic on species of Anguillula is 

 Harposporium Anguillulse, with respect to which Zopf confirms the 

 observations of Lohde, rather than those of Sorokin. It produces crescent- 

 or sickle-shaped conids borne on sterigmata, and resting-cells ; but its 

 systematic position cannot as yet be determined. 



Chroococcus turgidus is subject to the attacks of a parasitic fungus 

 belonging to the Ehizidiacese, to which Zopf gives the name Bhizophyton 

 agile ; while another species, B. gihhosum, attacks Desmidiacete [Cylindro- 

 cystis, Euastrum, Ptnium), Diatomacese [Pinnularia, Navicula), as well 

 as the ova of Rotifers. A new genus of Ehizidiacese, Septocarpus, 

 distinguished by the mode of germination of the zoospores, is formed 



* Scient. Mem. by meilical officers of the army of India, part iii., 1888, pp. 27-32. 

 t Nova Acta Aead. K. Leop. -Carol. Akad., Hi. (1888) pp. 813-70 (7 p]p.). 



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