34 THE ORCHID REVIEW. [FEBRUARY, IgI2. 
We dissent from the conclusion arrived at, but we have always 
maintained that Mendelism was nothing but a method of work. Formerly 
we used to read of the Mendelian Law of Dominance, Law of Gametic 
Purity, &c., and it was said that the great problem of the future was not so 
much the origin of species as the origin of unit characters. Then came the 
announcement that all that Mendel discovered was the Law of Segregation 
—which is simply the familiar dissociation of mixed specific characters ‘in 
hybrids under another name. Mendelism seems to be on a sort of 
inclined plane, and when it has reached the bottom of the slope it will 
probably show us some of the steps by which species have arisen through 
progressive development under the operation of natural selection, or the 
survival of the fittest. 
From the doctrine that the degree of fixity of a character—-we will omit 
the word specific—is not a measure of its utility to the organism we 
completely dissent. Nothing succeeds like success, and in the keen 
struggle for existence useful variations are those most likely to be preserved, 
and handed on to succeeding generations. In fact a character originally 
arising as a mere variation may in turn become a specific character, 
ultimately attaining generic and even ordinal significance. It is the history 
of evolution. 
If we must give an example in proof of the assertion, let us take the 
rostellum of an Orchid. As Darwin well pointed out, no such organ exists 
in other plants. It performs the double function of secreting a viscid 
substance which glues the pollinia to the visiting insect, and of preventing 
the pollinia from falling on to the stigma of the same flower. But it is only 
a modified stigma which has lost its original function, and the viscid 
matter, which dries almost instantly on exposure to the air, is only a 
modification of the viscid matter of the stigma, which remains moist for a 
long period. It is confined to the suborder Monandre, and may be said to 
have arisen as an adaptation with the development of that group. In the 
highly specialised Vandez a further modification has taken place, by which 
a portion of the rostellum is cut off to form the sti 
one of hyaline tissue, 
analagous to that by which a leaf js disarticulated and thrown off in 
autumn. 
And the rostellum has progressed to a marvellous degree of diversity in 
the different groups. At first a merely secretive organ, it has become a 
pouch-like body, enclosing the glands of the pollinia in Orchis; a double 
pouch in Ophrys; a profoundly three-lobed body in Habenaria, in which 
