Bibliographical Notices. 381 
The following closing words of volume iv. are well worth quoting, 
since the issue of plates to illustrate the work was alone required to 
make it take its place as the standard authority on the British Mol- 
lusea. We trust that no pains will be spared in the execution of 
these drawings. The generic illustrations which have been published 
in the earlier volumes have in many instances fallen short of what 
o _ they might have been; and even in the present volume, some of the 
engravings (for example, the figures of plate 7) are hardly worthy of 
that accurate artist, Mr. G. B. Sowerby :— 
«« And now, good reader, I should be sorry if you have complained 
of my being too voluminous. I never professed to make this a 
manual; nor have I yet quite done. Let me remind you of the 
advice given by Seneca (De Ira, lib. iii. c. 31. $3), ‘Age potius 
gratias pro his que accepisti: reliqua expecta, et nondum plenum 
te esse gaude. Inter voluptates est, superesse quod speres.’ 
«The next volume will complete the work, and contain an account 
of the few remaining Pleurobranchiata, the Nudibranchs (by Mr. 
Alder), the marine Pulmonobranchs, the Pteropods, and the Cephalo- 
pods, a Supplement to the volumes already published, and other 
useful matter, besides plates (plain and coloured) by Mr. Sowerby, 
to represent all the species and remarkable varieties of British shells. 
- Most of these plates are engraved, and the colouring is in progress.”’ 
Mind in Nature; or, the Origin of Life and the Mode of Develop- 
ment of Animals. By Henry James-Cuark, A.B., B.S., Ad- 
junct Professor of Zoology in Harvard University, Cambridge, 
Mass., &c. Illustrated; pp. v-315. D. Appleton & Co., New 
York. 1865. 
Tuis work has scarcely met with the attention, in this country, 
which it seems to deserve. It contains much interesting information 
respecting the lower animals, which is expressed in a clear and 
pleasing style. 
The Origin of Life is considered in the first five chapters, in the 
course of which the author adduces some experiments in defence of 
the hypothesis of spontaneous generation, and propounds his theory 
of the egg,—viz. that it is a ‘‘ bipolar animal,” .... ‘a globular 
accretion of two kinds of fluids, albumen and oil, which are always 
situated at opposite sides or poles,’ and separated more or less dis- 
tinctly from each other. Amongst the most remarkable modes by 
which an individual existence arises cited, is the derivation of vibrio- 
form bodies from the fibres of decomposing muscular and tendinous 
tissue. His assertion, at page 101, that “human digestion makes 
human flesh out of the decomposed meat of many different kinds of 
animals,’ requires some qualification, since the word decomposition 
is employed in the same paragraph somewhat in the sense of putres- 
_eence. The meaning of the word is wrested for the defence of 
spontaneous generation. 
The speciality of the second part is his treatment of the Protozoa. 
“The type of this division,’ he writes, ‘‘ is found in its relation to 
