230 TRANSACTIONS OF THE [MaY 22 



Nantucket*. Cretaceous and tertiary deposits are recognized 

 upon the former, by means of the fossils, but only tertiary and 

 later on the latter. The author also discusses at some length 

 the stratigraphy of each island and the probable changes which 

 have preceded their present condition. 



In 1889, Prof. Shaler published a paper " On the Occurrence 

 of Fossils of the Cretaceous Age on the Island of Martha's 

 Vineyard, Mass.,"f in which he discusses the probable origin of 

 the fossils and the dislocation of the beds. The fauna only is 

 described, no flora. 



In 1889, David White visited Gardiner's Island, Block Island, 

 Center Island and Martha's Vineyard, and collected a large 

 amount of cretaceous material, especially plants;];, which I was 

 kindly permitted to examine during the past winter, and was 

 thus enabled to idenitfy a large number of the species with those 

 which I had previously collected on Long Island and had become 

 familiar with from the cretaceous of Staten Island and New 

 Jersey. These discoveries proved to be of the highest impor- 

 tance, as we were thus enabled to trace the continuit}^ of the 

 cretaceous strata from New Jersey through Staten and Long 

 Islands to Martha's Vineyard, and to demonstrate beyond ques- 

 tion that the theory of Mather and subsequent olDservers in 

 regard to the eastward extension of the cretaceous formation 

 was correct, and that the geological maps of the region should 

 not only show the north shore of Long Island, but also part of 

 Martha's Vineyard as cretaceous§, and emj^hasized the proba- 

 bility" that certain limited areas of the New England coast could 

 also be referred to that horizon. 



The Long Island material upon which this paper is based 

 consists entirely of fossil jilants, no animal remains which could 

 be even provisionally referred to the cretaceous having come 

 under my observation. Fortunately, however, many of these 

 plant remains are in such a perfect state of preservation that 

 they may be readily identified with well known cretaceous 

 species, and the age of the strata in which they occur or from 

 which they have been derived can no longer be questioned. 



The total number of species represented in the specimens 



* Bull. No. 53, U. S. G. S. (1889). 



t Bull. Mus. Comp. Zool. xvi. No. 5, 89-97 (1889). 



i Am- Jouru. Sci. xxxix. 93-101 (1890), and Bull. Geol. Soc. Am. i. 554, 555 (1890), 

 with comments by Lester F. Ward, J. S. Newberry and F. J. H. Merrill. 



§ The two most recently published geological maps of the United States are 

 1st, by W. J. McGee, in 5th Ann. Rept. U. S. G. S. (1884). and, 2d, by C. H. Hitch- 

 cock, for the Am. Inst. Mining Eng. (1886). In each of these the north shore of 

 Long Island is recognized as cretaceous, but Martha's Vineyard is designated 

 as tertiary and ciuaternary only. 



