562 Dr. C. W. Andrews — New Egyptian Fossil Mammals. 



This is an important and ominous fact to be remembered by those 

 who, looking across the horizon separating us from the penultimate 

 changes in the world's history, see there a portentous ice age, swathing 

 half the northern hemisphere in ice, which actually, in the eyes of 

 some, crept up to the very threshold of our time. It is clear that the 

 facts and conclusions here discussed, so far as they go, give no kind 

 of support to such an hypothesis. They point unmistakably the 

 other way, namely, to a recent deterioration instead of an amelioration 

 of climate. We must go much further afield than the last 6,000 or 

 8,000 years if we are to find any substantial basis for that theory in 

 Scandinavia, and a fortiori in lands, like Britain, situated in lower 

 latitudes. 



V. — Note on the Species of Pal^omastodon. 

 By C. W. Andrews, D.Sc, F.G.S., British Museum (Natui-al History). 



DETAILED examination of the remains of fossil mammals from 

 the fluvio-marine beds (Upper Eocene) of the Fayllm has, in 

 several cases, shown that the number of species of the various 

 genera has been underestimated. This is especially the case with 

 Palaomastodon, of which originally only one species, P. beadnelli, 

 was recognised. Subsequently another form, P. minus, was named, 

 and now it has become necessary to establish at least two other 

 species, to one of which probably by far the greater number of the 

 specimens collected must be referred. 



The species of Palceomastodon fall into two sections, in one of 

 which the posterior end of the symphysis of the mandible is situated 

 considerably in front of the level of the anterior premolar, while in 

 the other it is only very little in front of that point. The first 

 group, moreover, is distinguished by the comparative simplicity of 

 the molars, in which the accessory cusps are scarcely at all developed, 

 and by the small size of the talon of the last lower molar ; into this 

 subdivision the oi'iginal species, P. beadnelli, falls, together with 

 a much smaller form for which the name P. parvus is now proposed. 

 The type-specimen of this new species is the right ramus of the 

 mandible, with the premolars and molars in situ, though somewhat 

 crushed. The posterior border of the symphysis is about 5-5 centi- 

 metres in front of the anterior premolar, which at once distinguishes 

 this form from the two species belonging to the other group. The 

 third molar consists of two transverse ridges, each composed of two 

 tubercles, and a smaller third crest consisting of a large outer and 

 a small inner tubercle ; there is no talon unless this third ridge is 

 so regarded ; there is a small intermediate tubercle in the anterior 

 valley, but otherwise accessory cusps are wanting ; the enamel is 

 very smooth, and the cingulum is practically absent. M. 2 is 

 trilophodont, but the last ridge is smaller than the others ; it 

 consists of an outer, larger and an inner, smaller cusp. The 

 dimensions (in centimetres) of the molars in this specimen are : — 



