724 GEOLOGY OF THE YELLOWSTONE NATIONAL PARK. 



LAURUS MONTANA 11. Sp. 

 PI. XCV, fig. 2. 



Leaves large, evidently coriaceous, elliptical-lanceolate, narrowed grad- 

 ually (?) to the petiole and (?) upward to an acuminate apex (?), slightly 

 unequal-sided in the upper part ; margin entire ; midrib thin, straight; second- 

 aries 5 or 6 pairs, alternate, the lower at a very acute angle, upper ones 

 slightly less so, all, but especially the lower ones, with numerous branches 

 on the outside, which join and form broad loops just inside the margin; 

 nervilles strong, percurrent, approximately at right angles to the secondaries ; 

 ultimate nervation not preserved. 



The leaf by which this fine species is represented unfortunately lacks 

 both base and apex, but is otherwise well preserved. It is 10 cm. long as 

 now preserved, and was, when entire, probably at least 14 cm. in length. 

 The width is 5.3 cm. As stated, it is a little (3 mm.) wider on one side of 

 the midrib than the other, making it slightly unequal-sided. The nerva- 

 tion is peculiar, consisting of about 5 pairs of secondaries, of which the 

 lower, on the narrower side of the leaf, begins well toward the base and 

 passes up to the middle of the blade, with numerous branches on the out- 

 side at right angles to the midrib. The lower secondary on the broad 

 side of the leaf is very thin and short, and anastomoses with a branch 

 from the lower portion of the second secondary. This latter is strong, and 

 passes above the middle of the leaf, and has only 4 or 5 branches on the 

 outside, all being at an acute angle with the midrib. The other second- 

 aries have 1 or more branches on outside, and also a number of strong 

 nervilles. 



This species appears to be related to some of the forms figured by 

 Lesquereux as Laurus grandis, 1 from California, and may possibly be an 

 anomalous form of this species. It is larger, more rounded, slightly unequal- 

 sided, and has quite different nervation. It also resembles L. californica Lx., 2 

 from the same place. 



Habitat: Yellowstone River, one-half mile below mouth of Elk Creek, 

 base of bluff; collected by F. H. Knowlton, August, 1888. 



'Cret. and Tert. Fl., PI. LVIII, fig. 3. 

 *0p. cit., PI. LVIII, fig. 8. 



