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THE AMERICAN NA TURALIST. [Vol. XXXVII. 



have usually smaller pinnules; there is some similarity with 

 Gkichcnia acutiloba Heer, the venation being much the same, 

 but the pinnules are smaller and more acute. The species is 

 named for its discoverer Mr. B. H. Saunders of Clifton, N. J., 

 who has collected a number of valuable specimens in the Clay- 

 Marls. 



The genus Gleichenia is a most interesting one. In the 

 living flora it has about twenty-five species, widely distributed 

 throughout the tropics of both hemispheres, subtropical eastern 

 Asia, and the humid regions of the southern zone. The fossil 

 species are equally numerous and widespread. Aside from those 

 forms from the Paleozoic and older Mesozoic which have been 

 referred to the Gleicheniacese, which reference is not altogether 

 conclusive, as they probably represent synthetic forms from 

 which the later species may have been derived, the genus 

 enjoyed a wide adaptive radiation during the lower and middle 

 Cretaceous. In the lower Cretaceous (Kome) of Greenland 

 Heer has described fifteen species of Gleichenia, only one of 

 which ranges as far south as the Potomac formation ; one other 

 occurs in the lower Cretaceous of the continental interior. By 

 the mid-cretaceous several of these I rreenland species had become 

 wide-spread, identical species occurring in such widely separated 

 localities as Europe and Kansas, or Europe, Greenland and New 

 Jersey; four of the Greenland species find their way south 

 along the Atlantic coastal plain and three reach Europe. Two 

 species occur in the Laramie after which the species disappear. 

 With the gradual refrigeration of Tertiary climates the Gleiche- 



age being the doubtful (iLic/iaua obsatra Kn. from the late 

 Tertiary (Esmeralda formation) of Nevada. This southern 

 movement probably continued until Glacial times sending the 



southern Europe into Africa. 



Pinus mattewanensis sp. now Fi<\ 4. 

 The well characterized impression of a single winged seed is 

 among the material from Cliffwood, N. J. Length 13.25 mm.; 



