FOSSIL PLANTS 155 



Spitzbergen referred by Heer to Ulmus braunii f but it seems impos- 

 sible that they should belong to this genus. They do not altogether 

 agree with Corylus, yet seem perhaps closer to this than to any other. 

 For the present they may remain under this name. 



Alnus corylifolia Lesq. 



Alnus corylifolia LESQ., Proc. U. S. Nat. Mus., vol. v, p. 446, pi. VH, figs. 

 1-4, 1882. 



The collection contains several perfect and beautifully preserved 

 leaves, as well as a number of broken examples, that appear to belong 

 to this species. They are of about the same size as the leaves in figs. 

 2 and 3 (loc. cit.) ; they have rather finer teeth, but otherwise do not 

 differ essentially. 



Alnus sp. 



pi. xxvin, fig. 2 ; pi. xxxni, fig. 4. 



The collection contains two specimens that appear to represent the 

 female catkins of an alder. They are well shown in the figures. 



Family ULMACE-ffi 

 Ulmus braunii Heer. 



Ulmus braunii HEER, Fl. Tert. Helv., vol. n, p. 59, pi. LXXIX, figs. 14-21, 

 1856. LESQUEREUX, Cret. & Tert. Fl., p. 161, pi. xxvii, figs. 1-4, 1883. 



I have some doubt as to the correctness of referring these leaves to 

 Ulmus, but the examples in hand are not to be distinguished from cer- 

 tain specimens from Spitzbergen and other localities that have been so 

 referred by Heer, 2 and I have thus regarded them. 



Family ACERACE^S 

 Acer trilobatum var. 



Pi. XXIX, fig. 2. 



The collection contains several broken leaves of a maple, one of the 

 best being figured. This appears to be one of the forms of the varia- 

 ble A. trilobatum. It lacks the upper portion, and its position, there- 

 fore, can not be definitely fixed. 



Family HIPPOCASTANACEJE 

 ^sculus arctica sp. nov. 



pi. xxx. 



Leaflets of large size, coriaceous, obovate-lanceolate, rather abruptly 

 rounded to an obtusely acuminate apex ; margin entire below, finely 

 1 F1. Foss. Arct., vol. iv, Abth. i, pi. xvi, figs. 5-8, 1876. 

 *F1. Foss. Arct., vol. iv, Abth. i, p. 75, pi. xvi, figs. 3, 4, 1876. 



