846 SUMMAEY or CUEBENT RESEARCHES RELATING TO 



juice of fruit with addition of urine or of ammonia and potassium 

 carbonate. He notes also the absorption of the mineral constituents 

 of the walls of the wood-cells when in immediate contact with the 

 hyphse of the fungus, while the organic constituents are dissolved 

 only by the ferment excreted. 



New Chytridiaceae.* — Since publishing his monograph of the 

 Chytridiacese,! Dr. C. Fisch has observed two new forms, one of which 

 deviates in several particulars from the typical structure of Chytridium. 

 It was found as a parasite on Mesocarpus, in the form of small flask- 

 shaped brownish receptacles, in length about half the diameter of the 

 Mesoca7-pus-M.a.ment. These are zoosporangia, with brownish thick 

 wall, not coloured by iodine. From the point of attachment to the 

 host proceeds an extremely fine mycelial filament, which penetrates 

 the Mesocarpus-cell, usually only reaching about its centre. The 

 contents of the zoosporangium consist of rather coarse-grained proto- 

 plasm, in which no nucleus was detected. The formation of the zoo- 

 spores is preceded by various changes in this protoplasm. The zoo- 

 spores are rarely more than eight in number, and agree in their 

 structure with those of Beessia. They are rather largo, composed of 

 finely granular protoplasm, imbedded in which is an evident nucleus 

 or nuclear structure. A single cilium springs from the somewhat 

 narrower anterior end. These zoospores move about rapidly in the 

 sporangium before the latter suddenly bursts by the separation of a 

 circular lid. After moving about rapidly for a considerable time in the 

 water, a pair of zoospores approach one another by their ciliated ends, 

 and coalesce completely. The resulting zygote contains at first two 

 nuclei, which soon coalesce into one. It then surrounds itself with a 

 cell- wall, and attaches itself to a MesocarpusSiament. By means of 

 a small appendage which pierces the wall of the host-cell, the zygote 

 empties its contents into the latter, and rapidly grows to a large cell 

 with membrane in two layers, the typical resting-spore of Chytridium. 

 These germinate after a short period of repose, and again produce 

 zoospores. 



The second new species is a Beessia, near to B. amoeboides, and 

 parasitic on a large Cladophora. 



The three genera Beessia, Chytridium, Bhizidium, present a series 

 in which the first species here described, perhaps the type of a new 

 genus, presents a connecting link. It is a typical Euchytridium, in 

 which the sexual function has not been lost. In the form and be- 

 haviour of the zoospores it is closely allied to Beessia ; while in the 

 structure and germination of the resting-spores, and in the develop- 

 ment of the zoosporangium and of the mycelial appendage, it is a 

 typical Chytridium. 



Nowakowskia, a new Genus of Chytridiaceae.t — Sig. A. Borzi 

 finds a parasitic fungus on Hormotheca, a new genus of algse, in such 



* SB. Phys.-med. Soc. Erlangen, xvi. (1884) p. 101 et seq. See Bot. 

 Centralbl., xxi. (1885) p. 167. 



t See this Journal, iv. (1884) p. 938, 



t Bot. Centralbl., xxii. (1885) pp. 23-6 (1 pi.). 



