PEOCEEDINGS OF GEOLOGICAL SOCIETIES. 
223 
A Victorian geologist Blandowski), in a paper read before the Eoyal 
Society of Victoria, explains the absence of the above-named sub-king- 
doms, by suggesting that the higher development and superior locomotive 
powers possessed by tlieir various members, allowed of escape during the 
deposition of that muddy sediment completely enveloping the more slug- 
gishly moving of their contemporaries. Such an hypothesis would of 
course involve a supposition of the muddy sediment having been suddenly 
deposited ; a circumstance hardly reconcilable with the fact that the beds, 
where fossiliferous, appear to contain shells pretty equally distributed 
throughout a considerable thickness, and are not, as would result from a 
sudden deposition like that supposed, made up of a thick layer of un- 
fossiliferous clay reposing upon a stratum of shells and organisms. Among 
the fossils, too, which I have by me, is a pecten, having an incrustation of 
bryozoa upon its inner surface — proof positive. I imagine that the shell 
must, after the death of its inmate, have lain during some time uncovered, 
or the growth of such parasite, in such position, could not possibly have 
taken place. And again, although every shell appears perfect and unworn 
by friction, yet in all conchifers and brachiopods the valves are disunited, 
and in univalves the operculum is invariably absent. If it is allowable to 
strain a point, I would suggest that previous convulsive movements had 
totally destroyed or greatly diminished the number of all the superior 
marine tribes in these waters ; and that the lower classes, escaping the 
catastrophes by virtue of their less sensitive organizations, and subse- 
quently multiplying greatly, simply that their enemies had been destroyed, 
Had grown to be more than ordinarily numerous. 
PEOCEEDINGS OF GEOLOGICAL SOCIETIES. 
Geological Society. — March 9. — W. J. Hamilton, Esq., President, 
in the chair. 
1. " On the Discovery of the Scales of Pteraspis, with some Remarks 
on the Cephalic Shield of that Fish." By Mr. E. Eay Lankester. 
The successive steps by which the genus Pteraspis came to be established, 
and the grounds on which the prevalent opinion as to its ichthyic nature 
rests, having been noticed, the author proceeded to describe in detail the 
scales, — which have lately been discovered at Cradley, near Malvern, and 
which alone were required to remove all doubt as to the affinities of the 
genus, — comparing them with those of Cephalaspis, to some of which they 
bear a great resemblance ; and he concluded by giving a description of 
the markings on the surface of the cephalic shield of Pteraspis rostratus. 
2. "On some Remains of Bothriolepis from the Upper Devonian Sand- 
stones of Elgin." By Mr. G. E. Roberts. Remains of a large Dendro- 
doid Cselacanth obtained by the author in Elgin were referred by him to 
the genus Bothriolepis. These consisted of two large casts of a central 
head-plate, with portions of the test ; a natural cast considered by him to 
represent the parietal, squamosal, scapular, and coracoid bones ; casts of 
the nasal bones, and teeth of the upper jaw ; together with tooth-like 
bodies, which were suggested to be teeth, originally situated in the poste- 
rior region of the mouth. The ornament borne upon the head-plate was 
next described by the author ; and, in conclusion, the affinities between 
