12 THE ORCHID REVIEW. : 
“EVOLUTION OF SPECIES BY NATURAL HYBRIDISATION.” 
“The experimental demonstration of natural hybrids shows clearly that 
intercrossing between different species is carried on in a state of nature, to 
a far greater extent than was formerly supposed ; and_ the comparative 
fertility of these natural hybrids would be of vital importance to them in 
their struggle for life. 
“If, as seems highly probable from . .. experiments with Orchids, 
it is the pollen only of hybrids that is impaired, and the capacity of the 
hybrid to bear seed crossed with the pollen of pure species remains practically 
unimpaired, it is quite clear that the natural hybrid has a part to play in the 
evolution of new species. 
““As we have already seen, hybridisation tends to increase variation, 
especially beyond the first generation, and, naturally, the more variable the 
offspring the better fitted would they be to adapt themselves to changed 
conditions of life. 
“Tf the circumstances changed rapidly and considerably, the variable 
offspring of the hybrids would stand a better chance in the struggle for life 
than the more uniform offspring of the parent species, which were themselves 
specially adapted to the old conditions. In this way, as conditions changed, 
new species would be evolved more {fitted to the new conditions of life than 
the old species, which they would gradually replace, and I venture to 
suggest that natural hybridisation is the most rapid of nature’s means 
towards that end.”—J. ¢., p. 181. 
LALIAS AND CATTLEYAS. 
Pror. HENSLow, on Tuesday last, in his lecture at the Drill Hall, drew 
attention to the many points of similarity that exist between Lzlias and 
Cattleyas, and to the ease with which they have been crossed with each 
other. The fact that in one case there are four pollen-masses, and in the 
other eight was not considered sufficient to justify a generic difference in 
the classification.—Gard. Chron., Dec. 17, p. 440. 
Will Prof. Henslow say what is sufficient? After uniting Cattleya and 
Lelia, how will he distinguish the new genus from Epidendrum and 
Broughtonia, on the one hand, and from Sophronitis, Schomburgkia, 
Brassavola and Tetramicra, on the other? And, if the number of pollen- 
masses is not to be taken into consideration in classifying Orchids, how 
does he propose to separate Octomeria from Pleurothallis, and both from 
Restrepia? Many genera of Orchids are big enough and difficult enough 
to classify without ignoring what is certainly a very useful character for this 
purpose. Pro. Henslow had much better leave Cattleya and Lelia where 
they are at present. 
RK. A. K, 
. 
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