THE BEGINNINGS OF LIFE. 469 



almost smooth, whilst its under surface was much more 

 complex (). Such specimens of Oxytricha and Pke- 

 sconia were, moreover, the only forms of Ciliata seen 

 in the solution from which the Chlorococcus vesicles 

 were taken. The origin of Oxytricha within the 

 filaments of Nitella has also been already referred 

 to 1 . 



Facts just as remarkable can be stated concerning 

 the different modes of origin of Vorticellse. Thus, 

 although Vorticella-cysts are so frequently derived from 

 encysted Euglenae, I have seen algoid vesicles budded 

 off from Vaucheria 2 (as well as others which have arisen 

 from the very common but protean Alga named Lynghya 

 muralis 3 ) also converted into Vorticella-cysts, and these 

 producing organisms in almost all respects similar to 

 those from cysts of Euglena origin. According to Dr. 

 Gros 4 , moreover, cellular bodies budded off from Moss- 

 sporangia may also undergo transformative changes in 

 all respects similar to those of Euglenae. 



In many other cases, however, Vorticellae seem to 

 arise in an altogether different manner. Instead of 

 being produced by the molecular transformation of 

 masses of matter which are at once converted into 

 full-sized though embryonic individuals, they are derived 

 from vesicles containing an animalized matter, which 

 bud out from, or are protruded by, certain vegetal cells 



1 See p. 404. 2 See Fig. 8 a,/, and p. 41 5. 



3 See Appendix D, p. Ix. * Loc. cit, pp. 448, 487. 



