THE 



aEOLOaiCAL MAGAZINE. 



NEW SERIES. DECADE IV. VOL. X. 



No. VIII. — AUGUST, 1903. 



0)-s,x(3rXJsr.A.Xj .^I^a?IOZLES. 



I, — Notes on an Expedition to the FAYt'M, Egypt, with 

 Descriptions of some New Mammals. 



By C. W. Andrews, D.Sc, P.G.S. 



IN the following note I propose to give a brief account of the 

 chief results obtained during an expedition to the Fayilm in 

 the early part of the present year (1903). The localities in which 

 collections were made lie to the north of the lake Birket-el-Kerun, 

 and are almost the same as those examined on previous occasions. 

 Practically nothing was found in the Middle Eocene beds, but from 

 those of Upper Eocene age a fairly large collection of vertebrate 

 remains, including several new forms, was obtained. A few 

 interesting things were also found in the Quaternary lake-beds 

 in the neighbourhood of Schweinfui'th's Temple (Qasr-es-Sagha) ; 

 these will be referred to more fully below. 



In the Upper Eocene bed the commonest forms appear to be 

 Palceomastodon and Arsinoitherium. Of the former the greater part 

 of a skull was found, showing that in cranial structure as well as in 

 the teeth this animal was a far more generalised mammalian type 

 than the later elephants. For instance, although the occipital 

 region closely resembles that of the elephant in essential points of 

 structure, nevertheless the enormous development of cellular bone 

 which gives the posterior portion of the elephant skull its peculiar 

 and characteristic appearance, has only just begun, and the temporal 

 fossEe are only divided from one another by a high sagittal crest 

 which extends forward to a point a little behind the orbits. The 

 hasis cranii and the facial region of the skull are much more pro- 

 longed than in the elephant, though here again there are no 

 differences in essential structure. Another peculiarity noticed in the 

 remains of Palceomastodon is the great variability in the dimensions, 

 even among adult individuals. When it is remembered that this 

 animal is probably the transitional stage between the small 

 Moeritlierium, about the size of a tapir, and the large longirostrine 

 Mastodons, this variability in size is particularly interesting as 



DECADE IV. VOL. X. NO. VIII. 22 



