Reviews—LEtheridge’s Paleozoic Fossils. 83 
In that vast maze of modern scientific nomenclature to which 
the multitude of specialists have given origin, in which the 
student of paleontology finds himself too often entangled, it is no 
smali matter to find some friendly clue offered ready to his hand, 
which if it will not in every case carry him safely out of the 
labyrinth, may at least give him a help in the right direction by 
showing him how to get at the reference he wants. 
It is only right to state, with regard to the work before us, that 
ten years ago it was quite ready and ripe for publication ; but owing 
to family illness and official duties having intervened, the work, 
which might have been issued in 1878, appeared only in 1888. As 
a consequence of this unfortunate delay, a very much larger Supple- 
ment has been found indispensable in order to bring the several long 
lists of fossils up to the closing date of 1886. 
Turning a critical eye to the work itself, we are at once struck by 
the important difference in arrangement between Mr. Htheridge’s 
Catalogue and that of its nearest predecessor, Morris’s Catalogue of 
British Fossils (1856). In the latter work we had a small 8vo. page 
only, and the species from the oldest Paleeozoic to the Recent were 
all arranged under their respective orders, families, and genera, the 
latter alphabetically, save in great groups, such as the Ammonites 
and the Brachiopods, which are simply subdivided into Paleozoic 
and Oolitic; or Oolitic and Cretaceous. In Mr. Htheridge’s volume 
we have a large quarto page subdivided into ruled spaces and 
columns, with the genera and species alphabetically arranged under 
the great zoological groups, and further into Cambrian and Silurian, 
Devonian, Carboniferous and Permian, whilst their range is indicated 
through a limited number of geological subdivisions by asterisks 
placed in the column headed with the name of the formation, as 
Harlech, Menevian, Lingula Flags, Lower, Middle, or Upper 
Devonian, according to the several horizons included on the page. 
Taking the genera and species, these are given with one or more 
references to the works published, but without localities, not as 
was the case in Morris’s Catalogue. 
Whenever a species has remained for some time under an earlier 
generic appellation than that by which it has since been recognized, 
it will be found duly recorded both under the old and disused genus 
and under the new and present recognized one, only the former 
reference is printed in ¢talics and the latter in roman type, with a 
cross-reference to the newer name. 
The earlier part of the Catalogue, up to p. 376, is provided with 
an admirable index. 
The Appendix which follows, covering about ten years down to 
the end of 1886, is more concise in its references as compared with 
the earlier part of the work and it has also an index to it. 
Without consulting this Appendix it might appear that the former 
part of the work was incomplete, which is not the case; but, taking 
a single group like the Sponges, a still newer revision of the genera 
has taken place subsequent to 1886, which will necessitate a 
further re-arrangement of these organisms whenever a new edition 
of this Catalogue shall appear. 
