

96 1). White — Cretaceous Plants from Martha? s Vineyard. 



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II I •'! 



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from its distant relation to other fossil crabs, afforded but little 

 aid in determining the geologic age of the terrane. However, 

 for some reason not given he withdraws his statement as to 

 their Cretaceous age. Dana, in his "Manual of Geology,"* 

 adopts the view generally accepted that the beds were of the 

 Yorktown (Miocene) Period. 



Except the map prepared for the Centennial Com mission, f 

 in which the western end of the island is colored Miocene, and 

 a notice of the opinion expressed before the New York Acad- 

 emy of Sciences by Professor Merrill,;}; in which he referred 

 the Gay Head strata to the Post-Pliocene or Quaternary, 

 nothing further seems to have appeared until the publication 

 (1889) of Professor K S. Shaler's excellent " Report on the 

 Geology of Martha's Yineyard,"§ in which the stratigraphy of 

 Gay Head is treated at length with full illustrations (p. 328- 

 332, pi. xxvi-xxviii). There the series exposed at Gay Head 

 received the name of " Vineyard Series." His conclusion (pp. 

 332, 333) is that this series " must be considered as belonging 

 to one great division of the Tertiary deposits ;" and when 

 speaking of its outcrop at Indian Hill he says : " This part of 

 the Tertiary series is certainly of later Miocene or Pliocene 

 age." Professor Shaler makes no enumeration or discussion of 

 the foseils, all paleontological data being left to a future report. 

 More recently, in a short paper on some Cretaceous fossils,! 

 which were obtained at several points in the drift on the more 

 eastern portion of the island, and which seem to indicate a 

 lower Cretaceous age, he points out the distinctions between 

 their probable source and the Yineyard Series, reiterating his 

 conclusion as to the Miocene or early Pliocene age of the 

 latter, and adding that u a careful study of all the exposures on 

 Martha's Yineyard containing Tertiary clays has failed to show 

 any distinct fragment of Cretaceous rock." 



It is obvious from the foregoing review that the prevailing 

 opinion favors a Tertiary, probably Miocene, age for the 

 "" Yineyard Series," and the re-deposition of the Cretaceous 

 invertebrates in the younger formation. 



The material collected last summer was found at several 

 localities and horizons in the Yineyard Series. The former 

 include the Kaolin clays at Peaked Hill in the western part of 

 the town of Chilmark, the carbonaceous clays at Nashaquitsa 



* J. D. Dana: Manual of Geology, ed. 1864, pp. 510, 511; ed. 18*75, pp. 

 494, 495; ed 1880, p. 495. 



f W. 0. Crosby: Report on the GeologicaLMap of Massachusetts, Boston, 1876. 



$ F. J. H. Merrill : Geological Structure and Age of the deposits at Gay Head, 

 Mass., Trans. N. Y. Acad. Sci., vol. iv, 1885, p. 79. 



§ Seventh Ann. Eept. U. S. Geol. Survey, pp. 297-363, pi. xix-xxix. 



|| On the occurrence of fossils of the Cretaceous Age on the Island of Martha's 

 Vinevard, Mass., Bull. Mus. Comp. Zool. Harvard Coll, vol. xvi, No. 5, 1889, pp. 

 89-97, pi. i, ii. 



