little more than the cost of paper and printing, we have here a work which, to the practical conchologist, more especially if he be likely to visit foreign climes, is of the greatest value. The volume contains 89 plates, in all embracing upwards of 630 figures, illustrating each of the genera into which the Mollusca are now divided, the arrangement being that published by Mr. Gray in the Synopsis of the British Museum. In the preface to this work, written by Mr. Gray, he says —
"The tracings from which these etchings of Molluscous animals have been taken, were originally made by Mrs. Gray for my use, with the view to their being added to my collection of figures of shells, and to aid me in their arrangement. Hoping that others may find such a collection of figures (many of them copied from expensive works, and brought together from sources not easily accessible to conchologists in general), as useful as they have been to myself, I induced Mrs. Gray to make slight etchings of them, which afforded her an interesting occupation during a period when she was confined to the house by ill health."
The book being thus superintended by Mr. Gray himself, and the figures apparently carefully collated with the originals, we can conscientiously recommend it to every student of Conchology. No one about to visit foreign climes ought to be without it, as with the opportunities he will then have of studying the animals alive, he will find this collection of good figures invaluable.
At the present day we believe it to be quite unnecessary to attempt to show the necessity for the conchologist to study the animals which form the shells. We shall content ourselves with pointing out one instance from the book before us, of the interest and value attached to such a study. Most of our readers are perhaps well acquainted with that beautiful, elegant and brilliantly polished genus of shells called Olives. If we examine one of these shells we find a strong and rather broad raised belt across the front of the shell; and round the spire we observe a deep groove or canal. How are these formed? Let us turn to plate 18, and we shall see that the animal has a singular acute reflected process in the front of the mantle, situate just behind the siphon; and at the hinder angle a thread-like elongated body, by means of which organs, as the shell is moulded as it were upon the body of the animal, it forms this belt and groove. The difficulty is thus solved at once, and a beautiful adaptation of means to an end is here pleasingly illustrated.
A second volume of this work is announced as forthcoming, and we have no doubt it will reflect great credit upon its amiable authoress, and do much to extend the knowledge of an interesting class of creatures, which have hitherto been too much neglected. W.
