114 ! Scientific Intelligence. 
lobul 
: Reproduction by conjugation of course had long been familiarly known 
in the lower Algz. But it was questioned whether this was really analo- 
gous to sexual reproduction, since what appeared to be similar spores are 
often formed of the contents of a single cell without conjugation. A 
choug shows that these are abortive spores, incapable of germination; 
while those which result from actual conjugation will grow into new 
plants, without further metamorphosis, Vaucher’s old observations to this. 
effect having been confirmed by Braun and Pringsheim. 
Thuret in the year 1850 
gh direct contact of the spermato 
dicecious species are perfectly decisive upon these points. He o wee 
the lively spermatozoids playing over the surface of the still-naked spore — 
tozoids actually penetrate the spore-mass; but there is no direct proof 
ndeed Thuret, in a very recent article (in Aun. Sci. Nat., ser. 4, 00 
7, 1857,) indicates the grounds of Pringsheim’s probable mistake. 
most interesting point in this last article by Thuret relates to the sudde 
In the higher Cryptogamia and in the Phanerogamia, Radlkofer’s 
treatise, though interesting for the history, offers nothing new re 3 
> 7 H w # 
referred to in the preceding paragraphs. But the subject is still to be 
continued, A. Ge 
6. Natural History of the Spongiadea—J. 8. BowErBank, mets" 4 
Highbury Grove, London,—eminent in this and related departments 
