14 /. ■'■ , i Floras \ th Am 



motion and Locality. Lower Cretaceous Band6tone, 

 ckbird Bill, Nebraska. (Dr. Bayden.) 



Sassafras crctaceum. (n. sp.) 



Li aves petiolate, decurrent al base, very smooth above, Btrong 

 nerved below; three-lobed; lobes entire and acute. The nervation 



! strongly defined; the central nerve straighl or nearly so; the 

 lateral primary nerves springing from ii al an angleof 30°; second- 

 ary nerves regularly arched till they approach the margin of the 



a, win n they are abruptly curved and run together. From 

 these the tertiary nerves are given off at a right angle, and from 

 these the quaternary nerves spring at a similar angle, together form- 



. network of which the areoles are sub-quadrate. 



is perhaps not certain that the relationship between this 

 mtiful fossil and the living Sassafras is as intimate as I 

 havt ed, for Dr. Bayden obtained no fruits with the 



leaves, though, from the abundance of the latter, it is to be 

 hoped thai they may yet be found in the same locality. Until 

 the fructification shall be procured, the su ion thai a species 



of onr modem genus Sassafras flourished as far back as the 

 epoch of the deposition of the Lower Cretaceous Btrata, may be 

 pted with a certain degree of mental reservation. It is 

 true, however, thai there is a mosl marked correspondence, both 

 in external form and nervation, between the living ami the 



il plants; the differences being no greater than we might 

 expect to find between species of the same genus. The nerva- 

 tion of the fossils is stronger and more regular, and the whole 

 aspeel of the leaf rather neater and more sy ctrical. 



With the material already before US, WO may at leasl infer 

 thai there was living in the American forests of the Chalk 

 period a Lauraceous tree, bearing trilobate leaves, having the 



leral aspect and nervation of those nfonr Sassafr 

 ., and /."■■ diiy. Lower < Iretaci 

 Blackbird Hill. Smoky Hill Fork, Nebraska and Kai 

 I Dr. I la;, 



