CRETACEOUS PERIOU.. 



459 



Sycamore), Hickory, Willow (Fig. 828), Oak, Poplar, Maple, Beech, 

 Fig, or the genera Sassafras, Liriodendron, Platanus, Juglans, Salix, 

 Quercus, Populites, Acer, Fagus, Ficus. Leaves of Sassafras, Tulip- 

 tree, and Willow are common. There were also species of Redwood 

 (Sequoia), the genus to which the " Big Trees " of California belong. 

 There were also the first of the Palms. Fossil palm-leaves, of the 

 genus Sabal, are met with on Vancouver's Island, in deposits which 

 have been pronounced Cretaceous. 



Coccoliths, calcareous disks less than a hundredth of an inch in 

 diameter (p. 135), which are now common over the bottom of the 

 deep oceans, contributed to the Cretaceous limestones, and are abun- 

 dant in the Cretaceous of the east slope of the Rocky Mountains. 



Fig. 825, Sassafras Cretaceum Newb., from the Dakota group, along with the three 

 following (Meek & Hayden); Fig. 826, Liriodendron Meekii Heer; Fig. 827, Legumi- 



Figs. 825-828. 



Angiosperms (or Dicotyledon's). — Fig. 825. Sassafras Cretaceum; 826, Liriodendron Meekii; 

 827, Leguuiino*ites Marcouanus ; 828, Salix Meekii. 



nosites Marcouanus Heer ; Fig. 828, Salix Meekii Newb. Large stumps of Cycads have 

 been found in Maryland, near Baltimore ; one is twelve inches in diameter and fifteen 

 high. (P. T. Tyson). 



The Cretaceous species of Platanus are mostly analogous to P. aceroides. Other spe- 

 cies from Kansas or Nebraska, Acer obtusilobum Lsqx., Sequoia Reich enbachi Heer, Se- 

 <puia formosa Lsqx., Liquidambar integrij alius Lsqx., Populites fagifolia Lsqx., Ficus 



