SEPTEMBER, 1909.] THE ORCHID REVIEW. 261 
appearance actually the original type of sweet-pea,’’ and we must leave it to 
our author to explain. He remarks: ‘‘ From these statements it may with 
great probability be inferred that the albinism of Mossiz Wageneri 
Gaskelliana alba and intermedia alba is due to the absence of one factor 
(say C); that in Harrisoniana alba and Schrédere alba it is the other 
complimentary factor which is wanting (say R); and that Warneri alba is 
heterozygous for the presence of one of them (being Rr, on this scheme). 
It is to be hoped that some Orchid grower will make the various unknown 
combinations and extend the series.”’ 
The other casetaken from Orchidology is called Monolepsis in Orchids, 
and refers to the notorious example of Zygopetalum Mackayi, which, when 
fertilised with various other Orchids, gives nothing but Z. Mackayi, an 
anomaly which proves no more explainable from the Mendelian standpoint 
than from any other. 
A question of great importance remains, namely the relation of Mendelism 
to Evolution. The names of Darwin and Wallace naturally occur in this 
connection, and we read, ‘‘ Had Mendel’s work come ‘into the hands of 
Darwin, it is not too much to say that the history of the development of 
evolutionary philosophy would have been different from that which we have 
witnessed.”’ We also read of the ‘‘various plausible but frequently 
unsatisfying suggestions put forward, especially by Wallace.” A remark on 
another page may be taken in this connection. ‘‘ The difficulty that some 
feel in realising the significance of Mendelism arises from the habit of looking 
on the bodies of animals and plants as stigle structures.” But the knowledge 
that they are ‘‘ double,” or that two cells—it may be even from the same 
individual—unite to form the new generation, helps us little in tracing the 
evolution of species that breed true from generation to generation. 
True, it is pointed out that Mendelian discovery does not run 
counter to thé cardinal doctrine that species have arisen by natural selection 
—and we are heartily glad to find some common standing ground—but we 
also read that “the conception of Evolution as proceeding through the 
gradual transformation of masses of individuals through impalpable changes 
is one that the study of genetics shows immediately to be false.” We will 
omit the word impalpable—it matters not the amount, if only variation takes 
place—and enunciate our profound conviction that it is by this means that 
What are termed representative species arise. All species do not arise by 
hybridisation, nor yet by Mendelian segregation following hybridisation. 
One further remark in this connection we do not understand. Speaking 
of the general acceptance of the doctrine of natural selection by scientists, the 
author remarks there was the remarkable exception that systematists for the 
_ most part remain aloof. But two of the greatest systematists of the day were 
amongst its warmest supporters, namely Sir Joseph Hooker and the late 
