before the Linnean Society, May, 1873. 245 
of one and the same animal ; and (2) the homology of the organs 
of two different plants, corresponding to the homology, for in- 
stance, of the wing of a bird with the fore-leg of a quadruped. 
To the former class belong the various much-vexed questions 
on the distinétion between axis and appendages, arising in the 
consideration of the flowers of Conifers as of many other or- 
ders ; but it is the latter class with which we are now more 
when we find in a species, or group 0 species, some one 
organ acme modified in adaptation to special purposes, and 
thus differing or progressing from the forms prevalent in the 
genus or order to which it belongs, without retrogression ™ 
other respects, and if we allow no fallacy to creep in as to what 
is geneti , lope of the higher 
P genetically the same as the carpellary envelope eatassl 
ect in previous races ; for the presumed ancestors | 
are cryptogamic. He rests solely upon the supposition — 
