4f 
out raore sections to determine positively the prevail- 
ing strike of these oeds. The inciLmhent drift is very 
variable in thickness, and large erratics, from twenty 
to thirty feet in diameter, are seen resting on aiiart- 
zose sand. The author saw no grounds for concluding 
that any cretaceous strata occur any where in the is- 
land, nor could he find any fossils which api-'Oared to 
^ have been waslied out of a cretaceous formation into 
the tertiary otrata, as some have suggested. 
T,iv Lvell Droceeds to the consideration of the or- 
r^aric remains collected by hhnself in Martha's Vine- 
yard. 
Itemijalia.— A tooth, identified by Prof. Owen as 
the canine tooth of a seal 5 of wiaich tlie crown is fract^r 
ed. It seems nearly allied to the modern Cysto phora 
proboscidea. 
2. A skull of a walrus, differing froia the skulls 
of the existing snecies (Trichecus rosraarus, Linn.), 
with which it was corapared by Prof. Owen, in having on- 
Iv six molars and tv/o tusks, whereas those of the re- 
cent liave four raolars on each side, besides occasionally 
a rudimentary one. The front tusk is rounder than 
that of the recant walrus. 
