140 
TERTIARY VEHTERHATA OF THE FAYCxAI. 
'I’he aiitcvior ))rem(0ar {pm. 2) is a simple, blunt, somewhat laterally compressed 
cone, of which tlie anterior slope is much shorter than the posterior. This latter is 
worn into a broad flat surface looking slightly inwards. There are no accessory cusps, 
but the cingulum is fairly well developed, especially on the inner side, where it is 
often somewliat crenulated or divided into small separate prominences. The next 
tooth {pm. d) consists of a larger outer and a somewhat smaller inner cusp arranged 
transversely. There is a small ])03tero-interiial cusp, lying behind and closely 
connected with the inner main cusp : this posterior cusp may sometimes be nearly 
absent. The cingulum is well developed, especially on the anterior and posterior 
faces of the tooth, where it forms small projections. The last premolar [pm. 4) 
is a bilophodont tooth, each crest consisting of a pair of cusps — the outer higher 
and more com])ressed, the inner more rounded and coming into wear first. The 
inner cusps in this ]iremolar already show a tendency towards a V -shape, the 
point of the V being turned inwards ; this form is the consequence of the presence 
of obscure and imperfectly separated tubercles on the antero- and postero-external 
sides of the inner tubercles. The anterior accessory tubercle of the front V and 
the posterior accessory tubercle of the posterior V become fused with the cingulum 
of the anterior and posterior ends of the tooth respectively. The other accessory 
tubercles form a bridge across the main transverse valley. The cingulum is well 
developed on the ends and outer side of the tooth, where it is strongly crenulated. 
The molars m. 1 and m. 2 are trilophodont, each ridge being composed of a pair 
of cusps similar to those described as occurring in 4, the chief difference 
being that in m. 1 and m. 2 the posterior accessory tubercle of the last inner cusp 
is larger and, by its union with the posterior border of the tooth, forms the first trace 
of a fourth transverse ridge. The cingulum is well developed, particularly on the 
inner side of m. 2. The last molar may be said to consist of two transverse crests 
and a talon. The anterior accessory tubercles of the inner cusps are especially 
well developed. The talon consists of three tubercles, of which the innermost 
is much the largest, and the outer two are sometimes imperfectly divided. The 
crenulated cingulum is well developed, particularly on the anterior and inner 
faces. 
The above account of the upper teeth applies to specimens referred provisionally to 
P. headnelU, but which may probably belong to F. wintoni : this applies to both 
the skull figured on PI. XII. and to the upper teeth figured on PI. XIV. fig. 2. 
The species being founded mainly on the form of the mandible and of the last lower 
molar, ic will not be possible, in most cases, to determine the skulls and upper teeth 
with certainty till specimens have been found associated with the mandibles. 
Upper Milk-dentition (PI. XIII.). — The u])per milk-teeth are preserved in the 
specimen upon which the account of the front of the skull is founded. In this, in 
addition to remnants of the base of the milk-incisor, there are on the left side three 
