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THE BEGINNINGS OF LIFE. 



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;rfectl 

 ^gish ; in tfc 



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times even a 



ce 



wliile tk 



contents pro- 

 lish oil-drops, 

 e cavity, aod 

 times even a 

 ■d-cells of the 



Iready had »=^ 

 ,ponaseedby 



shall subseqtt'"" 

 ^cities of ; 



ffitl 



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nd of *e 

 is to be 



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Bef"'^ 



179 



Zjgnemacea originate in tlie same way as those of (Edo~ 

 gon'ium^ with the single distinction that in the former 

 the contents of two chambers become united to form 

 one seed-cell/ 



■ b 



A mode of production of zoospores different from 

 that already described by Agardh, and resembling more 

 closely that by which the seed-spore of (Edogontum is 

 produced, is now known to take place in Achlya pro- 



■a curious little plant first discovered by Prof. 

 Goodsir, on the gills of certain gold fish which were in 

 an unhealthy condition. It was formerly thought to be 



■ars somewhat 



vesicles; the 

 )f deep greet 



appearSj first a species of Conferva^ but it is now regarded by the 



M. J. Berkeley and others as mer 

 or aquatic form of a Mucor. This^ as on^ of the simplest 

 Jdnds of Fungi, has been made the subject of a most 



careful 



Uno-er 



When 



beginning of the combination, the cells are filled with finely granular 

 contents, in which we see arise, during the progress of the union, shining 

 drops, at first very small and distant, gradually growing larger, coming 

 m contact and coalescing, so that the intermediate contents almost en- 

 tirely disappear, and the complete spore appears filled merely with a 

 mixture of oil drops of the most varied size. During this process the 

 colour of the cells changes from green to a light yellowish brown. 

 Vegetative cells with homogeneous green contents originate subse- 

 quently through transformation and division of the contents of these 

 oleaginous seed-cells/ (Loc. cit. p. 202, and PL I, 11.) In connection 

 With this subject, also, we may call attention to the fact elsewhere 

 (Linn. Soc. Trans, xxv. 1865, p. 84) mentioned, of the large amount of 

 free fat frequently existing within the intestinal canal of many of the 

 Fi-ee Nematoids, which appears to result from the more or less direct 

 transformation of the cellulose taken as food. 



' 'Einiges zur Lebensgeschichte der Achlya prolifera,' in 'Linn^ea,' 

 ^843,t.iv. 



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