130 Prof. G. Lindstrom—On the Operculate Corals. 
and clear, but some of the later ones, especially plate x., are not 
quite so satisfactory. 
Paleontologists in this country may sometimes think that specific 
titles are conferred by continental authors where a less marked 
differentiation would meet the case. At page 112 M. de Loriol, 
whilst complimenting Mr. Hilton Price upon the value of his work, 
“The Gault,” takes exception to his suggestion that many fossils, 
which are more or less identical, have different names in England 
and on the Continent. The author thereupon challenges the paleeon- 
tologists of this country to make some use of their immense Gault 
collections, to prove or disprove these statements. 
We suspect that the Gault is not the only formation where such 
is the case, but when the challenge is generally accepted, many 
preliminary arrangements will have to be made as to the meaning 
and value of terms, before anything like international paleontology 
can hope to be a success. 
II.— Om pr PaLmozo1sKA FoRMATIONERNAS OPERKELBARANDE KORAL- 
LER, AF G. Linpsrrom. Med nio Taflor. Bihang till K. Svenska 
Vet. Akad. Handlingar, Band 7, No. 4, Stockholm, 1882. 
On THE OpERCULATE CoRALS OF THE Patmozoic Formation. By 
G. Linpstrém. With 9 Plates. Appendix to the Transactions 
of the Royal Swedish Academy. 8vo. pp. 112. 
N this memoir Prof. Lindstrém has brought together a complete 
description of all the known species of those peculiar fossil corals 
which are distinguished by the remarkable feature of having one or 
more movable valves or lids, attached to the margins of the calice, 
which probably served as a covering and defence of the soft parts of 
the animal. This abnormal feature gave rise in past times to much 
misconception respecting the characters of these fossils, and certain 
species were, till a comparatively late period, referred to the Brachio- 
poda, though, strange to relate, some of the earliest writers who 
noticed these forms—Born and Guettard for example—placed them 
in their true position amongst the corals. 
All the operculate corals possess one or more plane outer surfaces ; 
and that on which the coral rests on the sea-bottom during its earliest 
growth, and from which, in many instances, root-like processes are 
given out, is termed by Lindstrém the under-side (bottensidan). 
Within the calice this under-side carries the largest septum. The 
side opposite, whose inner wall has the septal fossula, is named the 
upper-side (uppsidan) ; the two other sides are right and left, ac- 
cording to their position to the left or right of the under-side. The 
so-termed coste of the outer surface (not in the operculate corals 
merely, but in almost all the Paleeozoic corals) differ fundamentally 
from the coste of the Secondary, Tertiary, and recent corals, which are 
only continuations of the septal plates beyond the walls of the 
corallites, whereas in the Paleozoic forms, these vertical ridges 
actually occur in the interval between the two septa, and, as a dis- 
tinction, should be termed ruge. The rootlets are usually developed 
