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CYSTOSPERMEiE.

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 trueConferva; but before admitting any species as such, it isnecessary that it should undergo a rigorous examination ; forwe find placed among the Conferva proper many species havingno relation whatever with those near to which they are placed,but are referrible to some others of the genera belongingto 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 elderand Harvey amongst the Conferva properly so called. Thefirst 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 anew generic name, it would have been better to have reservedfor 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 unadvisablethat the term Conferva should ever be employed merely in ageneric sense —that a wider meaning ought to be extendedto the word—that it should be employed in the same manneras the term Zoophyte, and made to embrace the filamentousdivision of the Alga; and the second is, that there is noreason founded in right, why this term of Linnams shouldbe 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 productionswhich ought to be referred to it — Alga widely differing inessentials having constantly been placed under it.

Five of the six species of Prolifera described by Vaucherare certainly to be referred to the genus Vesiculifera, thesixth 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 themwith any degree of certainty. The following is Yaucher’saccount of the reproduction of the genus Prolifera, which, it