190 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 7, 



or even driven up the shore by the field of ice pressing upon them, 

 and heaped upon ice which had reached there previously. 



I do not think that this explanation differs from that given by Sir 

 Charles Lyell for similar phenomena. In the Lapland river Muonio 

 I have myself seen stones of several hundredweight perched at the 

 top of ice-heaps between 20 and 30 feet above the level of the 

 water, where the spring-flood has been opposed by islands lying in 

 its way. 



The largest travelled block I saw upon Oland was also near Borg- 

 holm ; it was 28 feet long by 22 broad, and stood about 8 feet above 

 the soil. It was flat and somewhat quadrangular at the top. 



Stockholm, 30th June, 1856. 



January 7, 1857. 



J. D. Rigby, Esq., W. Peace, Esq., and W. H. Baily, Esq., were 

 elected Fellows. 



The following communications were read : — 



1. On the DiCHODON cuspidatus, Owen. 

 By Professor Owen, F.R.S., F.G.S. &c. 



[Plate III.] 



In June 1847 I communicated to the Geological Society of London 

 a description of certain teeth and portions of jaws of an extinct Artio- 

 dactyle Mammal, from the Upper Eocene sand of Hordwell, Hants, 

 from which were deduced the dental characters of the genus Dichodon 

 and of the species cuspidatus^. 



The parts described were of an immature individual, retaining, 

 probably, the deciduous molars ; and having, certainly, acquired, in 

 the upper jaw, only the first and second true molars, and in the lower 

 jaw only the first true molar. The second true molar in that jaw 

 was just beginning to appear above the alveolar border ; the crown of 

 the third true molar was calcified in the upper jaw, but not in the 

 lower one, — not sufficiently, at least, to give the true form of its 

 crown. 



I have since been favoured, by the experienced and indefatigable 

 palaeontologist. Dr. Wright, of Cheltenham, with the opportunity of 

 examining and describing an instructive portion of the right ramus of 

 the lower jaw of the Dichodon cuspidatus containing the three per- 

 manent molar teeth, in situ, and thus supplying the tooth, m 3, which 

 was wanting to complete that part of the mature dentition of the 

 genus. 



This specimen was found by Dr. Wright near Alum Point, Isle of 

 Wight, in a bed of greenish tough tenacious clay. No. 35 of his 



* Quart. Journ. Geol. See. vol. iv., 1847, p. 36, pi. 4. f. 2-6. 



