

562 The American Naturalist. [June, 
Oxyn. greenoughi. Fig. 45 shows the stout form of the whorls better 
defined, and pilz of this subseries as compared with the oxynotum sub- 
series. 
n. lotharingum. Fig. 46 shows the smaller size of this species, and 
the aA of the pile. The involution of the whorls is, however, 
greater than in any preceding species. 
Oxyn. oppeli. Fig. 47 shows the extremely involute form of the Middle 
Lias. The stout whorls indicate that no great amount of degeneration had 
taken place. It may have been a direct descendant of greenoughi. 
The Age of the Gay Head Bluffs at Martha’s Vineyard.— 
At the last annual meeting of the Geological Society of America, Mr. 
Lester F. Ward remarked: ‘‘ My principal object in coming to this 
meeting was to listen to this paper, as I was associated with Mr. White 
in his work and am deeply interested in it. 
‘“ I desire merely to emphasize the great importance of the results at 
which he has arrived. Not until the past season has anything definite 
been known of the fossil flora of Martha’s Vineyard, the few fragments 
figured by Hitchcock not having been determined, and having no 
geognostic value. As Mr. White has remarked, the ablest geologists 
in the country have long been at work upon the question of the age of 
the Gay Head beds, and, as shown by the older as well as by recent 
papers, especially those of Professor Shaler, great differences of opinion 
and doubt as to their age have prevailed. 
‘ The discovery by Mr. White of undoubted baoo fossil plants 
has settled that question as far as the particular strata from which these 
plants were found are concerned. In all his recent papers, including 
the one read before the Society on Thursday last (pp. 443-452), Pro- 
fessor Shaler has insisted that all except the very base of the Gay Head 
section is Tertiary and even Miocene or Pliocene. 
“ Ido not pretend that the entire section at Gay Head and Nasha- 
auitsa cliff is necessarily Cretaceous. The plants were found in the 
Gay Head section near the middle, and it is very possible that, 
considering the extent of the beds and the length of the section 
the overlaying strata may be Tertiary, even Miocene. But if 
if there is a great thickness lying above these beds, so there is a 
great thickness lying beneath them, and therefore the section must 
settle the age of these beds than all that has been done before. 
Pipers extreme old age of this form is marked by decrease in the amount of involution 
ew and als 
y the loss of the prominent hollow keel. 

