456 Scientific Intelligence. 
Under the head of Reproduction by Seeds, Mohl gives an interesting 
and critical account of the development and structure of the pollen an 
the ovule, and of the origin of the embryo. ‘The latter arises by cell- 
multiplication of the germinal vesicle, a cell produced by free cell- _ 
formation in the embryo-sac usually before the pollen-tube has reached 
tion of it, and the formation of the embryo from the apex of the pollen- 
tube itself, as taught by Schleiden, are wholly repudiated ; and indeed 
the Schleidenian doctrine may now considered as thoroughly de- 
molished, by the direct observations of Amici, Mohl, Muller, Hofmeis- 
ne. 
The Cell as an Organ of Motion is considered as respects movements 
of individual cells through the agency of vibratile cilia, as respects the 
directions and curvature assumed by organs, and as respects movements 
by irritation of stimuli, &c., giving an excellent summary of our know- 
2dge on these points, with much admirable criticism; which want of 
space prevents us from noticing in detail. Our notice will have served 
its purpose if it direct attention to a treatise, small in compass an 
erate in price, but of the highest authority on these subjects of 
common interest to all naturalists and physiologists. Mr. Henfrey’s 
name is a sufficient voucher for the faithfulness of the translation. But, 
with equal correctness, the German might have been rendered into 
more flowing and idiomatic English. Pak 
2. Dr. Hooker’s Flora of New Zealand.—The third part, which has 
now appeared, carries this work from the Ericaces to the Orchidace®, 
and the plates from pl. 41 to 60. A. 6. 
he Oak- Vegetation of America, (Americas Ege-vegetation, §c-) 
abridged from two popular lectures delivered before. the Association of 
Natural History of Copenhagen, by Prof. LigsMan. Translated 
Dr. Watuica.—This is reproduced in Hooker’s Journal of Botany for 
Dec. and January last, and is a very interesting article, especially that 
part of it which relates to the oaks of Mexico, where the author trav- 
elled and collected extensively. Prof. Liebmann is now, we believes 
the successor of Prof. Schouw, the celebrated writer on the Geography 
of Plants, of whose lamented decease we have recent intelligence. 
4. Martius, Flora Braziliensis, Fasc. XI, Liepsic, 1852, pp- 79, fol», 
with 24 plates. This new part of the Brazilian flora, the publication 
ich is again actively resumed, contains the Piperinee, a class 
+ 
e 
ant, the 
4 'perace Me ae 
jes; Pi orphe, 4 species; Enckea, 4 species; Peltobryon, oa 
<n Ser ie empecics ; Ottonia, 19 species. Besides bre peek 
trations of this family, a single physi ical plate represen 
in the primeval foreiaa ‘of Braz AL eee oe ee ee Sean 
