NO. 2151. FOSSIL PLANTS PROM FLORISSANT— KNOWLTON. 263 



(6 mm. in diameter), and slightly concave, and presents an appear- 

 ance identical with that to be observed in the twigs and small 

 branches that are so abimdantly "cast" by the living cottonwood 

 trees (Pojyulus monilifera, etc.). 



The appearance of branching to be observed in this specimen is 

 imdoubtedly due to the presence of another raceme which lies imder 

 the larger example in such a manner as to make it appear as a branch 

 of it. 



POPULUS, species. 



Plate 16, fig. 4. 



Type.— C&i. No. 34,753, U.S.N.M. 



The specimen here shown, which is from the Hambach collection, 

 appears to be a large though evidently immature catkin of Populus. 

 It is from the base of the catkin, as evidenced by the 1 cm. long por- 

 tion of the stem below the last or first pair of capsules. The portion 

 preserved is about 5 cm. in length, but it is difficult to decide whether 

 or not it is aU present, and it is probable that it was very much longer 

 when perfect. 



It is quite possible that this may represent the immature stage of 

 Populus crassa, since, as may be seen on comparing the two figures, 

 it is evident that the main rachis is of about the same size, though the 

 individual pedicels are much shorter than they are in P. crassa. It 

 is not of very great importance in any event, and is given merely to 

 show that the various stages of the fruits of Populus were preserved. 



Family BETULACEAE. 



CARPINUS ATTENUATA Lesquerenx. 



Carpinus attenuata Lesquereux, Rept. U. S. Geol. Surv. Terr., vol. 8 (Cret. 

 and Tert. Fl.) 1883, p. 152, pi. 27, fig. 10. 



A single example in the Hambach collection. It is smaller than 

 the figure given by Lesquereux but does not otherwise differ essentially. 



CARPINUS FRATERNA Lesquereux. 



C'arpimis fraterna Lesquereux, Rept. U. S. Geol. Siirv. Terr., vol. 8 (Cret. 

 and Tert.) 1883, p. 152, pi. 27, figs. 12-14. 



Several fine specimens in both the Scudder and Hambach collec- 

 tions. One in the former collection is much larger than any of the 

 figures given of this species, but it does not otherwise differ. 



BETULA TRUNCATA Lesquereux. 



Betula truncata Lesquereux, Rept. U. S. Geol. Surv. Terr., vol. 8 (Cret. and 

 Tert. Fl.) 1883, p. 150, pi. 28, figs. 7, 8. [Alnus truncata on plate] 



The Hambach collection contains a single leaf of this species, this 

 being of the same shape and nervation as figure 8 (referred to in the 

 synonymy) , but is a little longer. 



