90 
EE VIEWS, 
vidson has not yet finished his elaborate monograph on the Brachio- 
poda. 
Among the Lamellibranchiata there have been numerous papers 
scattered through the British and foreign serials. Clark has placed us 
under many obligations by the publication, in a single octavo volume, of 
his valuable malacological essays on the British Mollusca; while the 
American conchologists have added vastly to the amount of new species, 
and Dr. J. E. Gray has kindly prepared genera and sub-genera, into 
which they ‘ ‘ drop’ ’ quite naturally. The (6 Shells and their Inhabitants” 
of the Brothers Adams still makes its occasional appearance, enriching 
doubtless in a high degree the purse and pocket of the benevolent pub¬ 
lisher; but up to the present without any sign of coining to a conclusion. 
Then we have weighty contributions from that vast shell-house, the 
“ Museum Cumingii,” monthly making their appearance in doubtful 
Latin, in the “ Proceedings of the Zoological Society of London,” and 
shortly afterwards rendered useful through the philanthropy of a Beewe, 
dressed in decent English—that would be better if it did not exactly 
follow the Latin—and embellished with first-rate lithographs; and last, 
but not least, we have British Museum Catalogues, and a Catalogue of the 
Catalogues; some of them just published; others in the press. We 
do not hold Yan der Hoeven or Clark liable for this great mass of matter, 
and, therefore, we do not grumble at this part of the bibliography not 
being quite up to the ever increasing standard of the day. Among 
foreign contributions we would notice the prize essay of Cailliaud ‘ ‘ On 
Boring Mollusca he considers the operation to be purely mechanical 
in Pholas, Teredo, &c., while he allows that others, as Saxicava, Gas- 
trochoena, &c., bore by means of an acid (vide “ Transactions of the Dutch 
Scientific Society of Haarlem,” Part xi. 1856). The recent discovery 
by Troschel of the existence in Dolium of free muriatic acid, settles the 
question of acid, occurring in some Molluscs at least, for ever. The very 
strange genus Eurcella wanting a trace of the valves, so universal a dis¬ 
tinctive mark of Lamellibranchiata, is not mentioned. 
The development of Chiton is not alluded to, and though the various 
stages have not been satisfactorily observed or recorded, yet the papers 
by Clark in the “ Annals of Hatural History,” and that by Loven in the 
“ Proceedings of the Boyal Swedish Academy” for 1855, are well 
worthy of a perusal. The species selected by both these observers was C. 
cinereus (Z.); the young larva moves about by the aid of a circle of cirri, 
which would appear to correspond to those on the velum of other young 
Gasteropoda. The number of ova discharged by a single Chiton is up¬ 
wards of 2000, and are about 1-100th of an inch in diameter. Our author 
places the Chitons, without any hesitation, among the Cyclobranchiate 
Mollusca, as surmised by Cuvier; and the development determines this po¬ 
sition as the true one. As Clark’s observations were very hastily made, 
the details were by no means as fully elaborated as we could wish, and 
we know no subject that stands more in need of original investigation, 
and that would be more likely to reward the patient observer. Loven’s 
memoir may be taken as a pattern to work by. 
