8 
HEP OUT OP THE 
curious and problematical fossil body known as the Aptychus or 
Trigonellites of Parkinson. Being free from any investing 
matrix they are more valuable to the Paleontologist than the 
Yorkshire examples of this fossil previously in the Museum, 
from the Oolite Quarries at Malton. 
In local Geology the Collection has been enriched with a 
splendid example of the Lepidotus semiserratus, or a scale fish 55 
of the Whitby Fossil-Dealers. This fish, along with many other 
choice Lias fossils, has been obtained in exchange for the Society’s 
spare duplicates of Foreign Shells, the duplicates consisting 
almost entirely of specimens that have accumulated from the 
successive contributions of Mr. Joseph Clark of Cincinnati, 
with Vvdiose cordial approval the exchange in question has been 
carried out. 
Mr. Hailstone has presented the Museum with a Saurian 
Vertebra from the Lias of Whitby, exhibiting a very remark¬ 
able structural peculiarity, the area of one of its articulating 
surfaces considerably exceeding that of the other. The Society 
is also indebted to Mr. Robt. Atkinson for a very fine speci¬ 
men of fossil wood from the Lias of the Coast. Various additions 
have been made to the general Geological Collection from the 
British Natural History Society, among the most important of 
which are a series of choice fossils from the Magnesian Lime¬ 
stone of Humbleton Hill, Durham, and a collection of specimens 
illustrating the fossils of the upper green sand in the neighbour¬ 
hood of Cambridge. 
At the meeting of the British Association held at Liverpool, 
in September last, the Keeper of the Museum gave a description 
of two fossils in the Museum of the Yorkshire Philosophical 
Society, which are believed to be unique. One of these, a new 
species of Saurian from Whitby, he described under the name 
Teleosaurus ischnodon,* and to the other, a new fossil Quad¬ 
ruped from Herne Bay, he gave the name Platychoerops f 
Richardsonii. 
On the same occasion he was able to lay before the Associa¬ 
tion some highly important additional evidence relating to the 
* Ischnoclon, feeble-tootk 
f riatyclicerops, wide-faced Hog, 
