ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 783 



Catenaria SoroMne. The sporangia are always terminal. The unicellular 

 mycelium with fine filaments, the zoosporangia, zoospores, and zygospores 

 are described. The two species especially studied were Nephromyces 

 Molgularum from Molgula socialis Alder, and Nephromyces SoroJcini from 

 Liihoneph-ya eugyranda Lacaze Duthiers. M. Giard believes that the 

 fungus is of use to the Tunicate which they infest, in helping to break 

 up the waste products which would otherwise soon obstruct the ductless 

 kidney. 



Plasmodium of Badhamia and Brefeldia.* — Mr. A. Lister finds Bad- 

 Jiamia utricularis and Brefeldia maxima very favourable species for observ- 

 ing the phenomena connected with the plasmodium of the Myxomycetes 

 The Plasmodium of B. utricularis can be kept in constant streaming 

 movement on various kinds of woody fungi for more than a year, often 

 covering large spaces, and it may with great facility be thrown into the 

 sclerotium or resting-stage, in which condition it can be stored away for 

 months, and brought back at any time into the active state by moistening. 

 When placed in a glass box it will soon crawl up the sides, and is then 

 in a favourable condition for observation. 



The application of small pieces of any digestible substance excites the 

 streaming of the plasmodium to an extraordinary degree ; but it possesses 

 a remarkable power of discriminating between different kinds of food. 

 Thus raw potato-starch is scarcely if at all affected, while if the starch 

 is swollen by moderate heat, it is rapidly digested. Cotton-wool is not 

 affected. The plasmodium can be raised from a sluggish and almost 

 quiescent condition to one of great activity by supplying it with Agaricus 

 campestris, Boletus fiavus, or the prepared hymenial sui'face of Stereum 

 hirsutum, while the coarser fibres of the latter fungus are more slowly 

 absorbed ; and this is also the case with Agaricus melleus and A. ruhescens, 

 and still more so with A. fascicularis. The digestive principle of the 

 Plasmodium is not confined to any special part of the mass ; it may take 

 place in the streaming interior or in the hyaline margia alone. 



The author is unable to suggest any explanation of the rhythmic 

 streaming motion of the plasmodium, or of the causes of the sudden 

 changes from a quiescent to a streaming condition, or of the impulse 

 which occasions the change into sporangia, though the latter is no doubt 

 favoured by hot weather. 



In Brefeldia maxima Mr. Lister records the remarkable observation 

 of an instance of spore-formation not confined by any inclosing wall. 



The presence of nuclei and nucleoli in the plasmodium of Badhamia 

 is easily proved. They are most readily detected by suddenly dipping 

 into absolute alcohol cover-slips which have been smeared with it, and 

 then staining with magenta. 



Mycological Notes.j — M. P. A. Dangeard follows up his researches 

 on the Chytridinese \ by giving the descriptions of several new species. 



Chytridium Brauni grows on Apiocystis brauniana ; the sporangia are 

 oval, and each forms at maturity from fifteen to twenty-five zoospores. 

 C. zoopMiorum resembles the preceding species, but the radicular system 

 is much more developed and more strongly branched; it attacks 

 Eotifers. 



* Ann. of Bot., ii. (1888) pp. 1-24 (2 pis.). 



t Soc. Bot. et My col. de France, Session Cryptogamique, 1887 (1888) pp. 21-5. 



X See this Journal, 1887, p. 284. 



