THE ORCHID REVIEW. 327 
THE CYPRIPEDIUM GROUP. 
SEVERAL years ago I commenced a study of the Orchidew, with a view of 
ining the relationship of the different groups to each other, and 
naturally commenced with the primitive group Apostasiee, a paper, 
entitled ‘‘A Morphological and Systematic Review of the Apostasiex,” 
being published in the Journal of the Linnean Society (Vol. XXV., pp. 211- 
243, t. 48), in which the structure, affinities, and geographical distribution 
of the group was fully discussed. .Subsequently, two species of the remark- 
able genus Neuwiedia came into cultivation, and flowered at Kew, and an 
account of its structural peculiarities was given in these pages two years 
ago (supra, II., p. 70). The Cypripedium group follows next in natural 
sequence, and as it occupies such an important position in gardens, an out- 
line of the species, and their natural arrangement, cannot fail to be 
interesting. And in order to make the account of the sub-order, Diandre, 
complete, a brief account of the Apostasieze may also be included. 
As regards the arrangement adopted, a few words must be said. Darwin 
has very well pointed out that a system of classification, in order to be 
natural, must be strictly genealogical, as the characters which indicate true 
affinity between any two or more species are those which have been 
inherited from a common parent. But as there is no written pedigree 
we can only trace community of descent by a comparison of structural 
g and diff es, carefully distinguishing between those characters 
which indicate consanguinity, or real affinity, and those which are merely 
adaptations for some special physiological effect, which latter are only 
analogical resemblances, sometimes between members of quite distinct 
groups. A difficulty presents itself here as to what are ancestral and what 
adaptive characters, but it is evident that the two are essentially distinct. ; 
Ancestral characters are those which have been the least modified in 
relation to the conditions of life to which organisms have been Tecently 
exposed, and consequently they may be recognised as those extending with 
the greatest amount of uniformity throughout a group, and subject to the 
least amount of variability. Moreover, they are invariably most apparent in 
embryonic structures, becoming most masked or obscured in those stages 
where the greatest amount of specialisation is devolved. And from this 
the img of rudi -y organs in a natural scheme of classification 
will be apparent. > : : 
Adaptive characters are those by which an organism keeps itself in 
harmony with changing conditions of existence, and these may produce 
similarities of structure in organisms far apart by ties of consanguinity, , 
for example, in the pollinary apparatus of Orchids and Asclepiads, which 
are adaptations for fertilisation by insects. Adaptive characters may in time 
