23 
Ursinus and Thylacinus Harrisii, is not a valid argument, because. 
those marsupials are carnivorous. The 2nd point urged by the 
author against the opinion, that the fossils belonged to insectivorous 
or marsupial mammifers, is in the nature and arrangement of 
the teeth. The number of the molars, he conceives, is a second- 
ary consideration ; but he is convinced that they cannot be separated 
in the fossil jaws into true and false, as in mammalia; the great 
length of the fangs, equal to at least three times the depth of the 
crowns, he conceives, is a strong objection to the fossils being placed 
in that class, as it is a character altogether peculiar and unexampled 
among mammals; the form of the teeth also, he stated, cannot be 
justly compared to that of any known species of marsupial or insec- 
tivorous mammifer, being, in the author’s opinion, simply tricuspid, 
and without any appearance of interior lobes. As to the canines 
and incisors, Mr. Ogilby said, that the tooth in D. Bucklandit, 
which has been called a canine, is not larger than some of the pre- 
sumed incisors, and that all of them are so widely separated as to 
occupy full five-twelfths of the entire dental line, whilst im the 
Dasyurus viverrinus, and other species of insectivorous marsupials, | 
they occupy one-fifth part of the same space. Their being arranged 
longitudinally in the same line with the molars, he conceives, is 
another objection, because, among all mammals, the incisors occupy 
the front of the jaw, and stand at right angles to the line of the 
molars. With respect to the supposed compound structure of the 
jaw, Mr. Ogilby offered no formal opinion, but contented himself 
with simply stating the appearances; he, nevertheless, objected to 
the grooves being considered the impression of blood vessels, though 
he admitted that the form of the jaws is altogether different from 
that of any known reptile or fish. 
From a due consideration of the whole of the evidence, Mr. 
Ogilby stated, in conclusion, that the fossils present so many import- 
ant and distinctive characters in common with mammals on the 
one hand, and cold-blooded animals on the other, that he does not 
think naturalists are justified at present in pronouncing definitively 
to which class the fossils really belong. 
Jan. 9, 1839.—Alexander Jack, Esq., Captain in the 30th Regi- 
ment of Bengal Native Infantry ; George Cunningham, Esq.,Harley- 
street; Rev. Samuel Wilberforce, M.A., Brighston, near Newport, 
Isle of Wight; Rev. William Bilton, of Port Hill, near Bideford; 
and Richard Clewin Griffith, M.D., Gower-street, Bedford-square ; 
were elected Fellows of this Society. 
A notice was first read on the discovery of the Basilosaurus and 
the Batrachiosaurus, by Dr. Harlan. 
The first remains of the Basilosaurus, which came under Dr. 
Harlan’s notice, were a vertebra and some other bones found in the 
marly banks of Washeta river, Arkansas territory. In the autumn 
of 1834, he examined another collection discovered in a hard lime- 
stone in Alabama, and consisting of several enormous vertebre, a 
humerus, portions of jaws with teeth, and some other fragments sup- 
