D. WHITE — CRETACEOUS PLANTS PROM MARTHA'S VINEYARD. 555 



of the middle Cretaceous of Greenland than to that of the Dakota group, there is every 

 reason for believing that it will prove to be largely identical with the rich but as yet 

 unpublished flora of the Amboy clays. The Gay Head flora indicates an age certainly 

 Cretaceous, and probably middle Cretaceous, for the terrane in which it was deposited. 



The occurrence of Tertiary elements in the fauna of the Vineyard series raises 

 the question as to whether the plant-bearing concretions are not exotic. The structure, 

 composition, number, size, position, and relations of these concretions to the contain- 

 ing matrix join in indicating their present existence in the place of their original 

 formation. Numerous stems and fragments, together with the eucalypt fruits, are 

 found in the matrix of the limonitic conglomerate. The extra-concretionary plants 

 found in the carbonaceous clays at various horizons, though mostly indeterminable, 

 seem to agree with the species found in the concretions. At Nashaquitsa the con- 

 cretions were observed by Professor Ward and myself apparently in the process of 

 formation, the leaves sometimes lying partly within the concretion and extending 

 outward into the homogeneous matrix. 



Similar plant-bearing concretions are found in the Amboy clays on Staten island 

 and in New Jersey. The extension of these middle Cretaceous clays as far eastward 

 as Glen Cove on Long island is now generally accepted. If the Vineyard series is 

 not itself a farther extension, it must, at least, have been derived in part, and witli 

 the minimum distance of transportation, from such a continuation of the middle Cre- 

 taceous to the eastward, along the south of New England. 



The present paper is the result of a preliminary study. Before the age and origin 

 of this series can be unquestionably determined, there is need of further work in all 

 branches of its paleontology, taken side by side with the study of its stratigraphy. 



Dr. J. S. Newberry : This is the first opportunity I have had to see any of the 

 plants spoken of by Professor Shaler, but there can be no doubt that they represent 

 the flora of the Amboy clays. I have been collecting fossil plants from New Jersey 

 for the last twenty years, have already some thousands of specimens, and have fifty 

 plates of this Amboy flora drawn and arranged for publication. I have traced the 

 Amboy clays from New Jersey across Staten island and along the north shore of Long 

 island to Sea Cliff and Glen Cove, and have long been of the opinion that the formation 

 extends the entire length of the island. Now, Mr. White has shown that it under- 

 lies Martha's Vineyard as well, for the leaves and fruits displayed on the screen 

 arc all found in the Amboy clays. I will not now say anything further about the 

 characteristics of the Amboy flora, only that it has some things in common with the 

 flora of the Dakota group, but contains many more plants found in the Atane beds of 

 Greenland and the Cretaceous clays of Aachen [Aix-la-Chapellej. Its geological 

 position is middle Cretaceous, or at the base of the White Chalk. 



Professor Lester F. Ward : 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 

 determinable and having no geognostic value. As Mr. White lias 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, espe- 

 cially those of Professor Shaler, great differences of opinion and doubt as to their age 

 have prevailed. 



