68 Bibliographical Notices. 
and receives only the clathrated forms C. rhombea and C, decussata, 
while the remaining section is placed in Modiolaria, Beck. Similarly 
Lucina has been divided, and its species distributed among the genera 
Loripes, Poli, Lucina, Brug., and Axinus, J. Sow. These changes 
appear to be for the better; but we are at a loss to understand why 
the same author who adopts these genera unites Modiola with My- 
tilus, Artemis and Cytherea with Venus, and Syndosmya with Scro- 
bicularia; for the four genera which he condemns are founded 
upon equally valid grounds with those which he adopts. 
There are two changes in specific nomenclature which appear 
especially to call for remark. The English Pinna, which has already 
been so frequently renamed, comes before us once more with a new 
title, as Pinna rudis. The author has given us no reason for the 
adoption of this name, which is remarkable, since another species 
has hitherto been considered to be the Pinna rudis of Linnzeus. 
Venus Gallina, Linn., is adopted instead of V. striatula, D’Orb.; 
but Mr. M‘Andrew has found these two species in company on 
several parts of the Spanish coast, each preserving its distinctive 
characters. Indeed the form of V. striatula from the same localities 
in which V. Gallina is found shows a greater divergence from that 
species than do the majority of examples of the same species as 
collected on our own coast. 
We have now freely handled the second volume of ‘ British 
Conchology,’ and called attention to points on which we are compelled 
to dissent from certain views which the author has adopted. Mr. 
Jeffreys can afford to challenge such criticisms. Indeed we have 
seen that he anticipated them. His work has too much sterling 
merit in it for him to fear the discovery of a few subjects of difference 
between the opinions of himself and those of his brethren of the 
dredge. We rejoice that a large class of persons who have hitherto 
been debarred from pursuing conchology by the expensive nature of 
the only descriptive work on the Subject will now find a standard 
authority brought within their reach ; while no experienced concho- 
logist will be able to dispense with Mr. Jeffreys’s work, or to take it 
up without finding its pages full of new and interesting matter. 
The School-Manual of Geology. By J. Berrr Jukes, M.A,, 
F.R.S. &c. Edinburgh, 1863. 362 pages. 
A Guide to Geology. By Joun Puitures, M.A., LL.D., F.R.S. 
&e. 5th edition. London, 1864. 314 pages. 
Both of the authors of the hand-books before us have supplied 
students with larger manuals, full of sound information in the chief 
branches of geology; and these more complete works have passed 
into two or more editions, keeping up with the progress of the 
science. Here, then, we have geologists, of great experience and 
good culture, expounding and illustrating the elements of their fa- 
vourite science, at large for advanced and special students, and in a 
less elaborate manner for the amateur and the beginner. This is as 
it should be. There are differences, however, in these little text- 
