THE PRINCIPLES OF BOTANY. 
315 
the food theory. Careful observation may, however, help us 
much in obtaining a decided unanimous conviction on this 
point; and my own experience, small when compared with 
that of men like Cruzel and Garreau (whose labours on this 
subject were rewarded by their colleagues as far back as 
1847) and others, corroborates the Continental explanation. 
THE PRINCIPLES OF BOTANY. 
By Professor James Buckman, F.G.S., F.L.S., &c. &c, 
('Continued froin p. 224.) 
The Amentales, which come next in order, forms a very 
interesting alliance, whether considered in reference to the 
structure of its members, or their distribution and uses. 
They may be diagnosed as follows : 
Declmous exogens, with scattered monochlamydeous flowers, 
single superior carpels, and large embryo lying in a small 
quantity of albumen. 
Professor Lindley states as follows :—“ The main distinc¬ 
tion between this and the Amentale alliance consists in the 
presence of albumen, and the flowers not being arranged in 
catkins. The former character, however, fails in several 
instances, especially in some Artocarpads and Hempworths; 
so that in reality the amentaceous inflorescence is the only 
difference that can be at present pointed out to separate two 
Alliances, which nevertheless appear to be really distinct if 
regarded as wholes. They touch most closely among the 
Planes and Artocarpads, which may be referred indifferently 
to the one Alliance or the other, for both have a quasi- 
amentaceous inflorescence, and Liquidambars agree with 
Planes in having albumen, while Artocarpus is said to differ 
from the mass of its order in the want of it. Artocarpus 
cannot, however, be separated from Ficus, nor Plantanus 
from Artocarpus, and this seems to justify the place assigned 
to Artocarpads and Planes in this arrangement.”— f The 
Vegetable Kingdom,’ p. 258. 
The learned professor divides the Alliance into seven 
natural orders, all of which contain some most interesting 
plants. We commence our description of some of them with 
a few notes on the Urticarias or nettle tribe. 
Nettles are well known to us through our native species, 
XLV. 21 
