50 
REVIEWS. 
sub-class has been a puzzle to all theorists; its natural affinities have ap¬ 
peared clearly to none of them ; and we find many eminent names differing 
widely as to where it should be placed. Messrs. H. and A. Adams say that 
“unwilling to separate the Branchiferous tribes, which undergo a metamor¬ 
phosis, and live in the water, from thePulmoniferous mollusks, whose young 
are like the parent, and which respire the free air, we have preferred to 
view the Heteropods as an independent sub-class between these two great 
divisions.” Now, we would recommend the authors, if they think this 
opinion of theirs likely to be the adopted one, to read the 456-7 pages of 
Mr. W. Clark’s British Marine Testaceous Mollusca. “ Conchology,” he 
there says, in all the triumph of victory—“ Conchology could never have 
settled this question : without the assistance of Malacology these tribes 
would always have remained wanderers, and be indefinitely the sport of 
hypothesis and then, with much apparent satisfaction, he places Ianthina 
in an united anomalous group immediately abutting on the Muricidous tribes. 
Well, even with the help of so much assurance, we still incline to believe 
that this class must still remain nomadic, must still be wafted hither and 
thither by every wind that blows, and is likely to be drifted by the various 
currents on all shores ; happy will it be when, Atlanta-like (we refer to one 
of the genera), it can anchor itself safely and securely in some quiet corner 
of the Molluscean group. Then some future Wiseman will laugh at our 
varied attempts to place our ideas standing upright upon their narrow ends. 
The plates of the typical species of each genus are delineated by the 
authors, and are very faithful representatives of nature. It would be unfair 
not to expect mistakes to be made in a work of such an extensive character, 
but we have detected none of any vital importance; a few that we have lighted 
upon might have been avoided, such as representing Ianthinidas as having 
a proboscidiform head, when both their neck and head are very short, 
though capable of evolving a retractile proboscis. 
We shall watch with unfeigned pleasure the progress of this work, which 
we see by the last number (xxv.), just received, has entered upon the Con- 
chifera, and wish the authors the success that their endeavours deserve. 
An Introduction to Entomology ; or, Elements of the Natural History 
of Insects. By William Kirby, M.A., F.R.S., F.L.S., Rectorof Barham ; 
and Willtam Spence, Esq., F.R.S., F.L.S. Seventh Edition. Onevol. 
8vo. Longman, Brown, Green, and Longmans : London, 1856. 
No work in the English language, we believe, has done more, than Kirby 
and Spence’s learned and popular Introduction, to spread the taste for Natural 
