io8 
NATURE NOTES 
field observations are well nigh useless, experiment on captive 
organisms practically inevitable. In botanical work, for instance, 
it is very difficult to keep a series of wild examples of a species 
under continuous observation whilst some of them are under 
conditions so differing as to amount to a control experiment. 
On the other hand, every experimentalist has experienced the 
difficulty of so isolating the conditions as not to interfere with 
the normal life of the species. 
Most critics, we think, would agree that in this task Darwin 
was eminently successful ; and yet practically the entire grava- 
men of the anonymous and belated work under notice is that 
Darwin, by the method of his experiments upon plants, placed 
them in such unnatural conditions as to vitiate altogether his 
results. “ A Field Naturalist’s ” main contention is, that in the 
experiments as to pollination with or without insect agency, the 
net used by Darwin, one with meshes one-tenth of an inch 
across, would be of itself sufficient to induce sterility or the 
incomplete maturation of pollen or stigma. 
Dimorphic Heterogony in the Primrose. Explained by Darwin as an 
adaptation for reciprocal cross-pollination, and by “A Field Naturalist” as a 
mere variation. 
\Kindly lent by Mr. Grant Richards, 
We do not know whether the ptiblisher hopes to attract some 
of the political devotees of the primrose, and certainly the whole 
trend of the work — which is, we gather, from the pen of a some- 
what elderly writer — of an extremely conservative, or perhaps 1 
we should say radically reactionary character. Had it appeared | 
twenty years ago we should have admitted that it presents a ^ 
cogent chain of destructive criticism ; but to-day the whole . i 
position is altered. Even throughout the years which separated '3 
the publication of the Origin of Species from that of Cross and Self- >5 
Fertilisation, viz., 1859 — 1876, though evolution was a triumphant * 
theory, natural selection was on its trial, and the progressive .j( 
acquisition of special contrivances for securing cross-pollination, : 
as an illustration of evolution by natural selection, could not be { 
