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MISS B, M. BRISTOL ON 



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Bripnn j^seudotriquetrum. In this form it was observed that the tubuhir 

 neck was absent, probably on account of the extremely thin leaves of the 

 host-plant, but there appeared to be a large bnlton-shaped outgrowth on the 

 surface of the wall of many of the cells. These bodies were always seen 

 from a surface and never from a lateral view, hence their connection with 

 tlie cell-wall could not definitely be established in this specimen, wliich was 

 mounted as a permanent preparation, l)at the alga bore a very strong resem- 

 blance to C. Arclierituium^ Hleron., as figured by Archer. In all other 

 respects, however^ especially in the characters of the chloroplast, this alga 

 agreed with C. Lemme^ and it was therefore regarded merely as a plnce- 

 yariety of the typical form. 



II. ChlokociiytriuxM biex>^e (Kkdjs), G. S. West, 



This species was first described by Klebs *, in 1881^ under the name 

 Endosplicvra biennis. The cells are spherical, lying in the intercellular 

 spaces of the sub-epidermal parenchyma of the liost. By successiA^e bi- 

 partition the contents of each cell divide into a number of daughter-cells, 



from each of which, by a further successive bi partition, 8-16 siniilar spherical 



zoogonidia arise which conjugate just at the opening of th^ mother-cell-wall 



to form quadriciliate zygotes. These germijuite and penetrate the tissues 

 of the host exactly as do the zygotes in ChJoroeliytriuin Lemnff\ but the 

 germinating tube and the part of the zygospore remaining on the surface of 

 the leaf soon die away. 



Wille t adds that the chromatophore forms a continuous parietal layer with 

 inwardly projecting ridges or rods and containing many pyrenoids^ so that 

 it is evidently of the same ty[)e as that described above for G. Lemncc. He 

 sees in the preliminary divisions of the cells before zoogonidia-formation 

 a modified form of veoetative division. 



III. ClILOEOCHYTRlUM TARADOXUM (Klebs), G. S. West. 



This species was observed by Klebs |, in 1881, in the dead or dying tissues 

 of Lemna trisiilcUy and was described by him under the name Scotinosphccra 



'oxa. He states that the cells are mostly spherical, showing at maturity 



a differentiation of the green protoplasm into cyliiulrieal or spherical masses; 

 and that,- as a result of very complicated changes in the cell, numerous, 

 biciliate, spindle-shaped^ asexual zoogonidia are formed. From Klebs's figures 

 it is seen that the cell-wall bears a conspicuous [leg-like thickening on one side. 



* Klebs, G- ^' Beitriige ziir Keuiituiss niederer Algenfonnen." Bot. Zeit. xxxix 



(1881) col. 329-300. 



t Wille, N. Die Xatiirlicben Pflanzenfamilien, i. Abt. i>, pp. 61, 66 (1897). 

 + Klobs, G. Bot. Zt^it. xxxix. ("1881) col. 300. 



