1883 .] Analyses of Books . 743 
at least, questioning the high rank which he has elsewhere 
claimed for the Composite. 
In the essay on the Arum, or Cuckoo-pint, we find some state- 
ments which may require closer examination. We read : — 
“ The Arum, however, has a still more cruel and insidious mode 
of procedure [no “ cruel and insidious mode ” having been pre- 
viously mentioned]. Its berries are poisonous, and very often, I 
believe, they destroy the little birds that they have enticed by 
their delusive prettiness. Then the body of the murdered robin 
decays away, and forms a mouldering manure-heap from which 
the young cuckoo-pint derives a fresh store of nutriment. I will 
not positively assert that it is for this reason the cuckoo-pint has 
acquired its poisonous juices ; but I cannot help saying that if 
any berry happened to show any tendency in such a direction, 
and so occasionally poisoned the creatures which eat it, it would 
thereby obtain an advantage in the struggle for existence, and 
would tend to increase the poisonous habit so far as it continued 
to obtain any further advantage by so doing. ... It has been 
asked why the birds have not on their side learnt that the Arum 
is poisonous ? The very question shows at once an ingrained 
inability to understand the working of natural selection. Every 
bird that eats Arum-berries gets poisoned, but the other birds do 
not hold a coroner’s inquest upon its body, or inquire into the 
cause of death. Naturally the same bird never eats the berries 
twice.” 
Let us, however, even at the risk of being pronounced unable 
to “ understand the working of natural selection,” examine the 
above deliverances a little more closely. Does every bird that 
eats Arum-berries get poisoned, irrespective of the dose taken, 
of the other contents of its stomach, or of possible constitutional 
differences ? In default of direct proof that such is the case, we 
must be permitted to doubt. We find that certain poisonous 
plants and certain animal matters are rejected as food by animals 
born and bred in the same district. How can this be except from 
a tradition — we can use no better term — that such substances are 
unwholesome ? Nor need we wonder how such a tradition can 
arise. A bird plucks a certain berry ; a beast browses certain 
sprays or twigs to a very small extent, and experiences more or 
less inconvenience. The knowledge of this fact is transmitted 
through the species, just as is that of other dangers, and the 
snare is in course of time avoided, however tempting the bait. 
It may, indeed, be asked whether “natural selection ” does not 
at times furnish too easy an explanation for phenomena observed. 
We find a plant elaborating an intense poison. We are told 
that this is a defensive measure : the plant kills or makes ill such 
creatures as prey upon it, and their kindred gradually learn 
caution. Unless this were the case the protection derived from 
poisonous properties would be but slight. The Arum-berry 
developes a poison and assumes a brilliant colour that it may be 
