CYSTOSI’EllMEiE.

185

especially in respect to those most interesting species whichI have described as producing true sporangia, without unionof the filaments.

This discovery of the identity of the mode of reproductionof the two families of Conferva hitherto treated of, leadsnecessarily to some general, and not unimportant conclusions.

Thus, it furnishes satisfactory evidence of the intimateand general connection which exists between these twofamilies, which include such a considerable proportion of thefreshwater Conferva, whereby much light is thrown uponthe often canvassed and much disputed subject of the ani-mality of the conjugating genera, for it proves, since inreality a conjugation takes place for the formation of alltrue sporangia, that both stand upon the same footing asregards their animal nature, a fact, which hitherto has neverbeen suspected, the vegetable character of the Cystospermeahaving long been considered as established, and that if thosespecies which exhibit the curious phenomenon of conjugationare really animal, so are all the true Conferva ; thus, if theseshould at any subsequent period be removed from the vege-table kingdom to the animal, so ought, as an inevitable con-sequence, all the other Conferva which I have included inthe group of Cystospermea.

But it appears to me that, from the fact disclosed of theunion and concentration of the contents of tivo cells in so manyConferva, no argument can be deduced either in favour ofthe sexuality or animality of the Conferva, numerous speciesoccurring, as already observed in the Introduction, in whichthis curious phenomenon is wholly wanting.

For my own part, I trouble myself but little with thedisputes about the boundaries of the two great divisions ofthe organised world, which forcibly remind me of the searchcarried on by ancient philosophers, for days and years, afterthe much-desired, but imaginary philosopher’s stone, endowedwith such all-pervading influence, or the equally fruitless in-quiry after perpetual motion, or any other of the wild chimeras,to which the minds of men have from time to time beengiven. It is my belief, that no such rigid boundary exists;