186 CYSTOSPEHME.E. 



for in living nature there are no abrupt unsightly chasms ; 

 all is uniformity, transition, design. 



To the group Cystospermea are to be referred all the true 

 Conferva; but before admitting any species as such, it is 

 necessary that it should undergo a rigorous examination ; for 

 we find placed among the Conferva proper many species having 

 no relation whatever with those near to whicli they are placed, 

 but are referrible to some others of the genera belonging 

 to the other divisions of the Conferva already established. 

 Thus C. alpina, C. purpurescens, C. zonata, C. punctata, 

 C> ericetorum, C. mucosa, are placed by Agardh the elder 

 and Harvey amongst the Conferva properly so called. The 

 first two, nevertheless, are Conjugatea, C. zonata and C. punc- 

 tata Spharoplea, and C. mucosa a Desmidium. 



It may be thought by some, that instead of instituting a 

 new generic name, it would have been better to have reserved 

 for the species included under it the old appellation of Con- 

 ferva. To the adoption of this course, two objections pre- 

 sent themselves ; the first is, that it appears unadvisable 

 that the term Conferva should ever be employed merely in a 

 generic sense that a wider meaning ought to be extended 

 to the word that it should be employed in the same manner 

 as the term Zoophyte, and made to embrace the filamentous 

 division of the Alga; and the second is, that there is no 

 reason founded in right, why this term of Linnaeus should 

 be perpetuated in any other way than that suggested, he, 

 and all who have hitherto employed it, having had no defi- 

 nite ideas respecting the exact nature of the productions 

 which ought to be referred to it Alga widely differing in 

 essentials having constantly been placed under it. 



Five of the six species of Prolifera described by Vaucher 

 are certainly to be referred to the genus Vesiculifera, the 

 sixth C. glomerata is of an entirely different nature. So im- 

 perfectly and inaccurately, however, are those species de- 

 scribed and delineated, that it is impossible to identify them 

 with any degree of certainty. The following is Vaucher's 

 account of the reproduction of the genus Prolifera, which, it 



