482 Dr. G. J. Hinde — Discovery of Marsvpites, etc. 



unknown, and must be sought in earlier horizons in the Ethiopian 

 region. 



The chief characters of the Barypoda are : — Full eutherian dentition 

 without diasteniata ; molars bilophodont, a character probably pro- 

 duced by the infolding of the ectoloph of increasingly hypselodont 

 teeth. In Arsinoitlierhim the molars are extremely hypselodont. 

 Premolars differ widely from the molars. In the skull the occipital 

 surface is strongly inclined forwards, and there are palatal and nasal 

 horns, the latter of enormous size in Arsinoitheriiim. The orbits 

 are open posteriorly. An alispheuoid canal is pi'esent. The brain 

 cavity is relatively much larger than in the Amblypoda. 



There is no entepicondylar canal in the humerus, and no third 

 trochanter in the femur. 



The fore-foot is much like that of the Proboscidea ; thus the 

 metacarpals alternate to the same extent as in Elephas, and the 

 scaphoid is closely similar. In correlation with the fact that 

 the radius is much smaller than the ulna, the difference in size 

 being greater than in Elephas, the cuneiform is large and seems to 

 have overlapped the magnum, while the scaphoid is relatively smalL 



The hind-foot differs widely from the Proboscidean type and 

 approaches that of the Amblypoda. The astragalus and calcaneum 

 both bear large fibular facets. The low and broad asti-agalus 

 articulates distally with the navicular and cuboid, the latter having 

 only a small surface of contact with the calcaneum. There wa& 

 probably a small tibiale. 



The feet were no doubt pentadactyl, the metapodials being short 

 and stout. From the form of the calcaneum it seems probable that 

 the heel sometimes rested on the ground. 



The systematic position of the other genus, Barytherium, is still 

 doubtful. It is clear that, from the character of its dentition, it 

 cannot come within the limits of the Barypoda as above defined ; 

 moreover, as far as can be judged from the distal end of the radius, 

 the carpal structure must have been widely different from both 

 that of the Barypoda and Proboscidea, and was more similar to 

 that of the Dinocerata. The humerus is of a most remarkable 

 form, and its peculiar character indicates that possibly the fore- 

 limb was used for digging or burrowing. For the present it will 

 perhaps be safest to place this genus quite provisionally in a sub- 

 division of the Amblypoda, the Barytheria, equivalent in value to 

 the Dinocerata. 



III. — On the Zone of Mabsupites in the Chalk at Beddington, 



NEAK Croydon, Surrey. 



By George Jennings Hinde, Ph.D., F.R.S. 



ON hearing that Mr. G. E. Dibley, F.G.S., had exhibited at tlie 

 June meeting of the Geologists' Association some test-plates 

 of Marsiipites from the Chalk of a new road near Eussell Hill, 

 I made inquiries of him, and he most kindly told me the particular 

 locality where he and others had obtained these fossils. As the 

 place was within an easy walk of my home, I visited it, in company 



