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THK GENUS CHLOROCHYTRIUM, 



19 



X, CHLOROCiiYTRTirM MooRET, N. L. Gardner. 



Among the form?* whieh were attrilnited to the species Cldorocystls Cohmi 



M 



ivioore 



realized that there was not a perfect agreement between the two alore, but 

 thounjlit that the two were proLahly forms of the same species. Gardner in 

 1917 has expressed tlie opinion that the two forms were not the same, and 

 suggested calling Moore's form C. Moorei. Tf I\roore's observations are correct, 

 and his paper gives ns no reason to suspect otherwise, Gardner is certainly 

 right in adopting this course, since the distinctions between the two are not 

 of such a kind as would bo induced by <litjfereuces in environment or by 

 individual variation. 



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The cells wore found growing partly embedded in the tubular fronds of 



no crowding, the cells w^ere entirely epiphytic. The colls are spliericid or 

 slightly elliptical, or they may be pear-shaped, with the pointed end 

 embedded between the Enteromorpha cells ; they ar(3 lG-26At in diameter and 

 are never irregularly compressed when crowaled. The cell-wall is destitute 

 of a neck-like projection, but in other respects the cells very closely resemble 



in structure those of C. CoJinii. 



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fonncd by successive biparlition 



of the contents of the inofher-cell ; tlie larger ones are spherical, with a 

 pyrenoitl, and are G-7 /x in diameter; the smaller are pear-shaped and vary 

 frotn 2'6-3*5/i in diameter. The escape of the zoogonidia is effected by the 

 liftino- of a circular lid, about 10 fi in diameter, from the surface of the cell. 

 Moore observed that in almost every case the zoospores escaped perfectly 

 freely and independently of one another, but tliat in a very few instances it 



enclosed in a delicate membrane 

 as in C. Lemnce. If there were such a membrane it must have been very 

 frail, and w^as suggested ratlier by the arrangement of the 'zoospores than by 

 any actual observation, Moore found that it always seemed to break up 

 before any reagent could be inlded to demonstrate it, and thought it quite 

 possible that nothing of the kind existed. Gardner's remarks on this point 

 are rather misleading, since he quotes this character as a distinction between 



' C. Moorei and C. Porplnjnr. 



appeared as tJiougli tl 



hey 



might have been 



No conjugation was observed in any of the physiological states induced 

 in the laboratory, l)ut Moore thought that other physiological conditions 

 might perhaps make it possi!>le. 



This form stands as an independent species chiefly on account of its 

 quadriciliate zoogonidia of two sizes, and of the circular lid w^hich lifts from 

 the surface of the cell to set free tlie zoogonidia. The shape and habit of 

 the cells are also different from those of C. Cohiii, though these characters by 



* Moore, G. T,, Bot. Gaz. vol xxx. (1900) p. 100. 



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