426 E. T. Newton—Pre- Glacial Mammalia. 
separated on the outer side by a short slit which is enlarged below. 
The outer surface of the crown is uniformly convex from before 
backwards in the region of these cusps, and becomes concave at 
their junction with the heel. From above, the cusps are seen to be 
very thick and solid, and to extend quite to the inner side of the 
tooth. There are no accessory cusps or tubercles, unless the very 
slight inequality of the flattened upper surface of the heel should 
be regarded as such. The hinder surface of the posterior cusp is 
flattened as if by attrition with the upper grinders. The portion of 
a small alveolus, behind the sectorial tooth, shows that this jaw had 
a small second true molar. The hinder portion of the fourth pre- 
molar has a sharp prominent keel, descending from the point of the 
cusp to the hinder border of the crown, and somewhat towards the 
outer side. On the inner side of this there is a flattened surface 
terminated below by the hinder edge of the tooth, which is raised 
into a ridge so as to form a kind of guard. There is no indication 
of a secondary cusp or tubercle upon this keel. Although the 
surfaces of the teeth have been channelled and grooved during the 
process of fossilization, yet, with a pocket lens, the original roughened 
surface is still visible on the intermediate portions. 
The following measurements of the Plas Heaton specimen and of 
the recent one in the British Museum are copied from the table given 
by Prof. Boyd Dawkins (Q.J.G.S. vol. xxvii.) ; the corresponding 
measurements of the “Forest Bed” lower jaw being added in the 
right-hand column. The lower jaw of the Glutton in the Museum 
of the Royal College of Surgeons is intermediate in size between 
this British Museum specimen and that from the “Forest Bed.” 
The measurements are given in fractions of an inch. 
Plas Heaton | Recent Glutton | “* Forest Bed” 
, specimen. in Brit. Mus. specimen. 
Depth or ramus below m, 1 ... 0:96 0°85 0:72 
iensuay ofan ely eae Mery 0-95 0-82 0-75 
Width % en Re, 0-42 0°34 0:30 
Height ,, Spaces 0-42 0°36 0°33 
Judging from the amount of variation, in regard to size, obsery- 
able among the recent individuals of Gulo luscus, and the identity of 
form between these and the “ Forest Bed” specimen, in as faras this 
is preserved, one cannot do otherwise than refer the latter to the 
same species. 
With regard to the particular horizon of the ‘“‘ Forest Bed Series ” 
from which this Glutton was obtained, we are happily in possession 
of exact information. Mr. Fitch purchased the specimen from the 
finder, Mr. W. Dix, of Mundesley: and my colleague, Mr. Clement 
Reid, has taken the trouble to visit the spot with Mr. Dix, and ina 
letter he assures me that “Mr. Fitch’s specimen was found half a 
mile 8.E. of Mundesley in the ‘ Forest Bed’ at the same horizon at 
which so many large bones are found.” ‘There is, therefore, no 
