4 PREFACE. 
tion of the shell which it inhabits,—I have aimed at little 
more than accuracy and simplicity, as far as the latter quality 
can be thought consistent with the rigid exactions of science. 
No attention has been given to the mere History of the 
subject; it is conceived that any disquisition on this head 
would more properly appertain to works of ultimate research, 
than to one whose sole intention is to make the pupil ac- 
quainted, in as tangible a form as possible, with results. To 
afford, at a cheap rate, a concise, yet sufficiently comprehen- 
sive, and especially a well illustrated school-book, has been 
the principal design. 
In conclusion, I have only to acknowledge my great in- 
debtedness to the valuable public labors, as well as private as- 
sistance, of Mr. Isaac Lea, of Philadelphia. To Mr. Thomas 
Wyatt, and his late excellent Manual of Conchology, 1 am 
also under many obligations. No better work, perhaps, could 
be put into the hands of the studeut as a secondary text book. 
Its beautiful and perfectly well-coloured illustrations afford 
an aid in the collection of a cabinet scarcely to be met with 
elsewhere. Le Ob ee 
PREFACE 
TO THE SECOND EDITION. 
In issuing a second edition of this ‘* Conchology,” in so 
very brief a period since the publication of the first large im- 
pression, the author has little more to do than to express the 
high pleasure with which he has seen his labors well received. 
The success of the work has been decided ; and the entire de- 
sign has been accomplished in its general introduction into 
schools. 
Many important alterations and additions are now made}; 
errors of the press carefully corrected ; many more recently 
discovered American species added ; and the work, upon the 
whole, is rendered more worthy the public approbation. 
E. A. P. 
