OU. ae ne ITIN MP 
the investigation of such large genera as this, of the variability of 
NOTICES OF BOOKS. 383 
any other Natural Order of plants whatever. We have no hesitation 
at all in saying that the Orchidee are the most difficult group, of any 
extent, in the vegetable kingdom, and that it is a matter of congratu- 
lation to botanists that Dr. Lindley should have taken them up in the 
present form. We may add that it is a disinterested contribution to 
science, and we fear a very costly one to the author. 
Of the genera treated, Calanthe contains thirty-eight species, most 
of them natives of India, and nearly one-half of the Himalaya moun- 
tains. Several are Japanese, one only is American, one ranges from 
India to Port Jackson, one inhabits the Society Islands, and another 
the Mauritius and South Africa. Limatodes contains five species, all 
Indian; Geodorwm nine; all, but one Australian species, are Indian. 
Of the fifty-two species contained in the above genera, fifteen were 
previously undescribed. ; 
The elaboration of the genus Oncidium is however in every respect 
the magnum opus of these Parts, and is alone a monograph of the 
utmost use. Whether we consider the number of species in cultiva- 
tion or the state of confusion the genus was in, both in our books and 
herbaria, it is a work of very great labour and application, and could 
hardly have been accomplished but for the author's talent for drawing; —— 
this enabled him to sketch, under the microscope, the important cha- = 
racters taken from the labellum, especially of many specimens of each — 
species, that were steamed and softened for the purpose, and to weigh. 
the characters at leisure. One hundred and ninety-eight species are 
described, divided into fourteen sections; of this great number only 
about a dozen are described as new, which is the best assurance not 
only of the author’s knowledge of the literature of the Order, but of 
the skill and care with which it is worked up ; for we need hardly say 
that there is a host of new habitats given, and new amended charac- 
ters to old species, and a great reduction of spurious ones. It is in 
whose species we have abundant proof in every stove forced daily 
upon our notice, that the intélligent systematist often pauses to con- 
sider whether the characters he draws from one or other class of organs 
are the most constant, and in this case he is tempted to ask at times 
whether any are. Dr. Lindley does not avoid this most dishearte 
point in his studies, but meets it boldly and well. He says, “ ‘In s som 
of the sections, whether artificial or natural, into which Oncidium 
