PROCEEDINGS OF THE SOCIETY. 69 
sharks of recent times, by way of illustrating the remains of the 
more ancient fishes. The President spoke of the appearance of 
these Heterocercal fishes in the Silurian Seas, and of their co-tem- 
porary appearance with the Ganoids from the commencement of 
the old Red Sandstone until the end of the Oolite period. After 
that time, the crushing (palatal) teeth that had been so 
common in the past ages of the geologic world passed away, the 
Sharks of the tertiary and more modern times being armed only 
with the sharp and cutting dentition so characteristic of these 
inhabitants of recent seas. The only known exception to this 
latter statement, being the Port Jackson Shark, and some of the 
Dog fishes and Rays (Raiede). The fact was referred to, that but 
fewremains of the Sharktribe are preserved in the various geological 
formations. The reason assigned for this fact, was, that the whole 
skeleton of this fish being cartilage and not bone, after death it 
would dissolve before it could become petrified. The address was 
illustrated by many specimens of teeth and vertebre belonging to 
geological and recent species. There was also a numerous collec- 
tion of teeth and scales of Ganoid fishes from the carboniferous 
and oolite formations. Amongst oiler microscopic illustrations at 
the close of the meeting, were sections of the scale of Lepidotus 
Mantelli, from the Wealden, Tilgate Forest; and the scale of a 
Ganoid-fish from the Coal Shale, Newcastle. In this object the 
perforations of the scale were pointed out, and the connection of 
each of these foramina by means of channels similar in appearance 
to Havyersian Canals. The whole scale exhibited lacune and 
canaliculi which appeared to assumethe appearance of Mammalian 
rather than of Ichthyic type. These cell-markings were grouped 
around the perforations like the concentric layers of lacunse 
around the apertures of the Haversian Canals in transverse sections 
of mammalian bones. The members were especially interested in 
a specimen of fresh water Shrimp so common in the wells of the 
town, and a beautiful oceanic form of Crustacean (minute Shrimp), 
Pontella, n. sp., a8 well as another exquisite microscopic object— 
the tongue ( Odontofore, Huxley) of the Ear-shell Mollusk (Haliotis 
tuberculata)—from Guernsey. 
Books Received, 
One Thousand Objects for the Microscope. By M. C. Cooke. 
This little’ work comes with peculiar fitness from one who ‘has done so 
much to popularise the study of Natural History: When we state that it 
