122 
The Irish Naturalist. 
May, 
pleadings for the neo-Darwinian position. It is positively stated (p. 240) 
that the sessile condition of the eyes is a primitive character in the Crus- 
tacea, whereas evidence for the appendicular origin of these organs is 
constantly becoming stronger. Again (on p. 264), the author, stating that 
the Peripatids are "the most typical instance of a transitional form that 
we know," implies that the family represents a direct link in the descent 
of myriapods and insects from annelid worms. No zoologist doubts that 
the Peripatids are, in several respects at least, transitional forms, but there 
are many reasons for disbelieving that they stand in an ancestral position 
to the tracheate Arthropoda. The paragraph on p. 37, summarizing the 
geological history of animal life, is seriously misleading, for the author 
states that "nowhere [in the strata] do we find the animals of our own 
time, or, at all events, only in the very latest periods of the earth's 
history." ' The persistence of certain generic types through many of the 
great periods to the present day — a fact which tells strongly in favour of 
the Darwinian position— would certainly not be inferred from such a 
sentence by the average reader. And despite the clearness of his style 
and the assurance with which he writes, considerable doubt as to his 
views on the course of evolution may remain in the student's mind. For 
while in many passages he rejects the theories of mutation and of discon- 
tinuous variation, he tells us (p. 158) that " the ancestors of all reptiles 
consisted of a pair of amphibians that reached special conditions, and so 
their offspring formed a new class. These amphibians lived about the 
end of the Carboniferous period.'' The conception of the evolutionary 
process implied in such a statement as this, can only be matched in the 
writings of some extreme modern neo-Lamarckians, or in the famous 
" Vestiges " of sixty years ago. 
The zoological portion of the book must thus be pronounced to a great 
extent untrustworthy. In the philosophical chapters with which it con- 
cludes, the translator seems to be more at home with his subject, and 
the author's arguments on the relations of Darwinism to the "problems 
of life," are put before the reader in a manner both forceful and vivid. 
Ivife, with its accompaniments of mind and will, is explicable, so our 
author urges, on mechanical principles, and since the whole organic 
world has become what it is by the unaided action of natural selection on 
fortuitous variations, any teleological factor is rigidly dismissed from the 
scientific conception of the evolutionary process. In our judgment, the 
neo-Darwinian position (in the author's sense of the " all-sufficiency of 
natural selection") is farther than ever from general acceptance, and we 
believe that were Darwin with us to-day, his reception of the light thrown 
on the course of variation by the work of De Vries and the Meudelians 
would be very different from that of the naturalists who claim to be ex- 
clusively his disciples. But despite his exclusively mechanical theory of 
evolution. Prof Guenther admits that consciousness must ever be at the 
root of all human experience. Dismissing with some impatience the 
ethical systems founded on biological theory, he warns science not to 
overstep her proper sphere of enquiry ; and, assuming finally a strongly 
