British Association for the Advancement of Science. 27 
Changes of Level.—Mr. Smith, of Jordan Hill, made some 
observations on the changes of level of land and sea, that have 
last taken place, instanced by the occurrence of recent marine 
shells and gravel at various elevations. He mentioned the shores 
of the Solway Frith, and of Ayrshire, the neighborhood of Pais- 
ley: also Portrush in the northern part of Ireland, and the late 
observations of Mr. Lyell, in Sweden. The alluvial clay of the 
Forth is elevated sixty fect, that of Essea one hundred and fifty 
feet ; indeed, recent shells have been found by Mr. Gilbertson in 
some places at an elevation of three hundred feet. On the shores 
of the Clyde, over a deposit of erratic blocks, is a stratum of shells, 
which contains fourteen new species not now found in the river ; 
this is a singular occurrence, as in other parts of Great Britain the 
erratic blocks overlie the newer Pleiocene strata, to which Mr, 
Smith refers this stratum. 
Silica in Plants.—Prof. Henslow stated, that he believed the 
object of the author was to prove, that all plants contained more 
or less silica; that the silica left after burning assumed different 
forms, according to the species of plants, and that this process 
might probably be applied to the investigation of the species of 
fossil plants. 
Goliathus Magnus.—A specimen of the Goliathus magnus, 
was also exhibited. This is the largest species of insect known, 
measuring three or four inches in length, and one and a half in 
breadth. It is also very rare, only three specimens existing at 
the present time in the cabinets of Europe. It was one of the 
rarest insects known. It had been offered for sale at the price of 
fifty guineas, and he had himself offered twenty guineas for a 
specimen. It belonged to the extensive family of the Cetonide. 
This family was one of the most extensive and best known 
groups of insects that we possessed, and afforded the best oppor- 
tunities for acquiring ideas of general arrangement. It contained 
six hundred species, only six of which were British. The family 
Buprestidae, perbaps equalled them in numbers. 
Wood in the Sea—The President then exhibited some wood 
from the new pier at Southampton, that had been attacked by the 
Limnoria terebrans. He had been applied to, by Capt. Du Cane, 
mayor of Southampton, for his opinion as to what was the ‘oat 
course to be pursued, as the existence of the pier was threatened 
by these devastating animals, He had recommended, that stone 
