98 



fruits of this species and from which the fossils are indistinguish- 

 able. This species has been found fossil at a number of localities. 

 The writer has recorded it from both Virginia * and North Caro- 

 lina ; t Mercer reports numerous specimens from the celebrated 

 cave deposits at Port Kennedy, Pa. ; | and the leaflets described 

 by Hollick § from the Maryland Pleistocene as Hicoria pseiido- 

 glabra may well belong to the same species. This comparative 

 frequency of occurrence in the Pleistocene would seem to indicate 

 that it was exceedingly abundant. Its presence in these deposits 

 can hardly be attributed to more favorable opportunities for pres- 

 ervation since other hickories like Hicoria rnininia and Hicoria 

 aqiiatica inhabit wetter situations and would seem to be equally 

 well situated for interment in river and estuary swamp deposits. 



As previously mentioned, the genus Hicoria is abundant in the 

 Pleistocene, additional American records being those of Hicoria 

 pec an, \^ Hicoria ovata^ Hicoria aquatic a, ^^"^ and Hicoria alba.\'\ 

 The latter is found in the remarkable Interglacial deposits of the 

 Don Valley near Toronto, Canada, and enables us to form some- 

 what of an estimate of the time involved in the geological changes 

 of the Quaternary, since with the exception of the occasional 

 carrying and burying of the nuts by squirrels, the normal rate of 

 migration which includes the factors of seed dispersal and rate 

 and time required to grow to bearing age, is comparatively slow 

 in this family. 



Juglans nigra Linne. 



The single nut of this species which was found is shown in 

 fig. 6. It is identical with the smaller nuts of the modern tree. 

 The husk was entirely rotted away and the surface largely 

 smoothed before entombment, the rugosities of the shell being 

 partially eliminated. It seems probable that the tree which bore 



* Berry, Torreya 6 : 89. 1906. 

 j" Berry, Journ. Geology 15 : 340. 1907. 



J Mercer, Journ. Acad. Nat. Sci., Phila. (II) 11 : 277, 281. 1899. 

 ^ Hollick, loc. cit. 221. //. ^2. f. /, ib, 17. 

 II Lesq. , Am. Journ. Sci. 27 : 368. 1859. 



^Mercer, loc. cit. 279. Berry, Journ. Geology 15 : 340. 1907. 

 ** Berry, Torreya 9 : 71. 1909. 



ffMercer, loc. cit. 281. Penhallow, Trans. Roy. Soc. Can. 10*: 73. 1904; 

 Amer. Nat. 41 : 446. 1907. 



