DECEMBER. 
273 
4 i 
than in darkness, and consequently that their diurnal respiration greatly preponderates over 
their nocturnal. The diurnal respiration of plants, which pours into the air considerable 
quantities of oxygen gas, happily compensates for the effects of animal respiration, which 
produces carbonic acid gas, injurious to the life of man. Plants purify the air injured by 
the respiration of men and animals. If animals transform the oxygen of the air into carbonic 
acid, plants take this carbonic acid back again by their diurnal respiration. They fix the 
carbon in the depth of their tissues, and return oxygen to the air, in reparation. 
“ Such is the admirable equilibrium which the Creator has established between animals 
and plants, such the beneficial communication which assures to the air its constant sound¬ 
ness, and maintains it in that stale of purity which is indispensable to support the life of the 
living creatures which cover the globe.” 
The second division, or that which relates to the classification and natural 
families of plan's, constitutes the major portion of the work, occupying upwards 
of 300 pages. In this the editor of the translation adopts, and we think not 
wisely. Dr. Lindley’s system as given in his “Vegetable Kingdom,” seeing that 
that of De Candolle is now universally adopted in this country. However, 
the leading characteristics of the most important natural orders are described, 
as well as many of the species, and the properties and products of some of these 
receive a considerable share of attention. Thus in Papaveracese, after stating 
the peculiarities of the order, the Opium Poppy is figured and described, and a 
short account is given of its products ; and so on with other natural orders. 
The third part, or that which is devoted to the geographical distribution of 
plants, fills rather more than forty pages, affords a very good idea of the vege¬ 
tation of different parts of the world, and will be read with pleasure as well as 
profit. 
It is but just to add that the translator has well executed a rather difficult 
task, and although there are some trivial errors and misprints, for instance in 
the spelling of the botanical names, the book is a good book, and will be very 
serviceable to those commencing the study of the subjects to which it relates, 
and of which it may be made the means of affording a very respectable know¬ 
ledge. 
OUR CONTEMPORARIES. 
The Botanical Magazine for November has plates of the following:— 
Brachystelma Barberies (Mrs. Barber’s Brachystelma).—An Asclepiadaceous 
plant discovered by Mr. Bowker (Mrs. Barber’s brother) in the valleys of the 
Isomo river, Kaffirland, but not yet introduced. It has a large depressed tuber, 
of the size of a Turnip, from which proceeds a very short stem, furnished with 
spreading, linear-oblong, acute leaves 3 or 4 inches in length. The flowers are 
collected in a sessile globose capitulum from 4 to 5 inches in diameter, dingy 
purple, speckled with yellow in the disk. The corolla is five-lobed, an inch 
across, and the lobes terminate in slender tails, an inch in length, which arch 
inwards and cohere over the centre of the flower. 
Nierembergia rivulciris .—A beautiful little species lately introduced from 
La Plata by Messrs. Veitch, but discovered upwards of thirty years ago by Mr. 
Tweedie, abounding by the sides of the Plate river within the high-water mark. 
It has slender creeping stems and nearly sessile flowers, with a broadly cam- 
panulate yellowish white limb, borne on a very slender tube from 1 to 2h inches 
in length, and of the same colour as the corolla, which is sometimes tinged with 
rose colour. 
Notylia bicolor .—A beautiful but very minute .Orchid, discovered by Mr. 
Skinner in Guatemala, and afterwards by Hartweg on Oak trees in the moun¬ 
tains of Comalapan. The whole plant does not exceed inch high, has some- 
what scimitar-shaped leaves, and slender, graceful, drooping flower-spikes 2 or 
