296 Dr. W. Pringsheim on the Germinution 



mother-cells, or the contents of the already formed spore^ give 

 origin to these other, rarer forms, in which the capabiUty of re- 

 production is likewise either permanently or transitorily secured 

 to the cell-contents. 



Examples of manifold forms of spores in the same species have 

 indeed often presented themselves to observers, but hitherto 

 have been mostly regarded as abnormal cell-formations, and no 

 further estimated. In spite of the slight attention directed to 

 these structures, many undoubted phenomena referable here 

 may already be indicated, of which, however, I shall only cite i^ 

 few. '« 



The contents of the individual cells appear to be capable of 

 producing new individuals in other ways than by the forms of 

 spores already mentioned, in the Spiroyyrce. Vaucher*, namely, 

 whose observations may be regarded as correct, even when not 

 yet extensively confirmed, saw the contents of isolated cells of 

 his Conjugata amjulata [Mougeotia genujlexa) transformed directly 

 into a young plant, without having first assumed a definite rest- 

 ing form, and emerge from the cell, as it wore born alive ; and 

 Dilhvynt, on the other hand, observed that this plant forihe4 

 seed in the same way as the rest of the Zygnemacese. The obserj^ 

 vation also on the division into four of the spores of Mesoem-pu^ 

 scalaris, made by Thwaites and published by IMontagneJ, is'to 

 be included here, like so many other observations of the division 

 of spores. But such a division of spores into inany daughter- 

 spores, does not afford any distinctive character of species or 

 genera; it is possible in all propagative cells of a great number 



* hoc. cit. p. 80. pi. 8. figs. 7, 8, 9. Here, the cell which grows into a 

 new Sjnrogyra, and which ordinarily, in the normal spores of the Zygne- 

 macese, is formed subsequently on the inside of two membranes thrown off 

 in the germination, appears to have been formed directly in the cell of the 

 parent plant, without these coats. 



t British Confervfe, London, 1809, p. 1 8. The passage runs : — " I have 

 since discovered the seeds of Conferva genujlexa ; they are large and glo- 

 bular, and not found within either filament as in Conferva jugalis {Spiro- 

 gyra jugalis), but in the connecting tube, which thereby becomes greatly 

 distended, as it is represented in iny supplementary plate. M. Vaucher 

 could not discover the seeds of this species, and of the nature of his obser- 

 vations I cannot form any conjecture." The figure of Conferva genujlexa 

 cited by Dilhvyn, as well as the reference to the ])assage in Vaucher, leare 

 no room for doubt that it was the Mougeotia genujlexa on which DillwMi 

 made his observations, and that Vaucher and Dillwyn investigated the 

 same plant. I will remark in passing, that, consequentlj% the seeds of 

 Mougeotia are not only known, but also represented by Dillwyn (op. cit. 

 Supp. pi. C), and then the distinction between the genera Mougeotia and 

 Mesocarpus founded on the want of spores in the former falls away. 



X Duchartre, ' Revue Botanique,' 184fi, p. 469, or the Report on this 

 notice in Mohl and Schlechtendahl's ' Botanische Zeitung,' 184fi, p. 498. 

 The Report agrees exactly with the text of the notice. 



