766 The American Naturalist. [August, 
GEOLOGY AND PALEONTOLOGY. 
The Origin of the Sycamore.—The American origin of our 
sycamore was long denied by European botanists, and was'only ren- 
dered certain by its discovery in a fossil state by Prof. Lesquereux in 
a late deposit of the Mississippi valley. Specimens were sent to that 
great authority on these subjects, Dr. Oswald Heer, of Zurich, who 
could find no characters by which to distinguish the fossil from the 
living form, and who regards this as a final settlement of the question. 
But through the researches of Lester Ward we now learn that the 
genus itself, the entire type of vegetation to which the plants belong, 
is American, and that numerous and strange archaic forms of this : 
type formed umbrageous forests on the shores of the great inland 4 
Laramie sea where the Rocky Mountains stand, and of the ocean at a 
time when it extended northward across what are now the great plains 
of the United States and Canada. (Proc. U. S. Nat. Mus., Vol. XL) 
M E aL ú; 
ae Ere EE Ay. 
The Cuboides Zone.—In a paper read before the Geol. Soc. - 
Am., Dec. 28, 1889, by H. S. Williams, the author concludes, after he 
a study of the Cuboides zone and the Tully limestone, that within 
narrow limits, geologically speaking, the point in the European time 
scale represented by the beginning of deposition of the Cuboides 
Schichten of Aixla Chapelle and Rüdesheim, is represented in New 
York sections by the Tully limestone ; and second, that the representa- 
tive of the fauna of the Cuboides zone of Europe is seen in New York, 
not only in the Tully limestone, but in the shaly strata for several 
hundred feet above. : 
. Therefore, if we wish to express precise correlation in our classifica- 
tion of American rocks, theline between Middle and Upper Devonian 
formations should be drawn at the base of the Tully limestone, to cor- 
respond with the usage of French, Belgian, German, and Russian 
geologists, who include the Frasnian, Cuboides Schichten, and cor- 
related zones in the Upper Devonian. 
. In discussing the subject Mr. C. D. Walcott remarked: “ Prof. p 
Williams' paper is of unusual interest, as he has shown very clearly 
that the theory of Huxley that there is no homotaxial relation between 
the sub-division of the geologic systems on the American and Euro- 
pean continents is not altogether correct. This study of the Cuboides 
