; 





I ■! ■• 



94 D. White — Cretaceous Plants from Martha? s Vineyard. 



illustrations of the six specimens that were figured. Certainly 

 nothing has been added meanwhile to the knowledge of the 

 matter gained a half century ago, and which may be summa- 

 rized in the fact that fossil dicotyledonous plants existed at Gay 

 Head. 



As a result of a visit paid to Martha's Yineyard last summer, 

 in company with Professor Lester F. Ward of the U. S. Geo- 

 logical Survey, by whose courtesy the material was referred to 

 me for examination, I was so fortunate as to find a large 

 number of specimens of plants, which, though generally rather 

 poorly preserved, will perhaps furnish important aid in solving 

 the vexed question as to the age of the underlying clays, lig- 

 nites and sands of Martha's Yineyard. In order, however, that 

 the facts about to be brought forward may take their true posi- 

 tion and color in the perspective of evidence and previous 

 opinions as to geological age, it will be well to make a brief 

 review of preexisting data and opinions. 



As early as October, 1786, Samuel West, in " A Letter Con- 

 cerning Gay Head,"* described the striking color effect and 

 the disturbance of the strata, and noted the occurrence of fossil 

 wood and bones ; and Dr. William Baylies, who aided him, 

 and whose letter followsf the other, agreed with Mr. West in 

 regardmg the upheaval of the cliffs as due to volcanic action. 

 He found what he considered to be five or six craters, and 

 observed the presence of whales' bones, sharks' teeth and petri- 

 fied shell-fish. The island is not colored on Maclure's map, nor 

 mentioned in his explanation.^: In 1824, John Finch§ ex- 

 j pressed the belief that the Gay Head clays, in common with 



the clays at Sand's Point on Long Island, Amboy in New 

 Jersey, and those of Cape Sable, Florida, Alabama and Missis- 

 sippi, were of the same age as the Alum Bay clays in the Isle 

 of Wight. The same year, Edward Hitchcock, in some " No- 

 tices of the geology of Martha's Yineyard and the Elizabeth 

 Islands,"| seemed inclined to consider the clays of Gay Head 

 and the Chilmark Cliffs (he visited the latter only) as equiva- 

 lent to the European Plastic Clay formation, and they were so 

 colored on the accompanying map. The same volume*j[ contains 

 a review of Conybeare and Phillips' "Outlines of the Geology 

 of England and Wales," in which the reviewer asserts, the 

 identity of the Plastic clays of Europe with those of Gay Head. 



* Samuel West: dated Oct. 9, 1786, Mem. Am. Acad. Arts, Sci., vol. ii, 1793 r 

 p. 147-160. 



\ 1. c, pp. 150-155. 



% William Maclure : Observations on the geology of the United States, explana- 

 tory of a Geological Map, Trans. Am. Phil. Soc, vol. vi, p.t. 2, 1809, pp. 411-428. 



§ John Finch: .Geological Essay on the Tertiary Formations in America, this. 

 Journal, vol. vii, 1825, pp. 31-43. 



|| 1. C, pp. 240-248, pi. iv. 1 1. c, pp. 203-240. 



