70 DESCRIPTION OF SPECIES. 



Lir i opliy 11 u m Beck w i t . li i i , Lesqx. 

 Plate X. Fig. 1. 

 Hayden'a "Ann. Eep.," 1876 p I-'-'. mentioned. 



Leaves large, square in outline, cut to near the base into two large diverging 

 lobes; lobes bilobate, obtuse; primary nerve very thick, continuous to a short petiole, 

 bifid at a short distance above the base, the divisions ascending to the obtuse point of 

 the upper lobes; secondary veins two, parallel, curved into the lower lobe, all with 

 few branches. 



The abnormal form of the leaves of this genus renders their descrip- 

 tion difficult. In this species, which may be a variety or deformation of 

 the following, the leaves are large, about 28 centimeters between the points 

 of the lower lobes, and nearly 20 centimeters from the base to the apex of 

 the upper. They are divided into two halves from the top to 4 centimeters 

 above the base by the splitting of the medial nerve under an angle of 40°, 

 and each division is cut at the side in two short obtuse lobes separated by 

 a broad sinus. The lower lobe, nearly at right angles to the midrib, is trav- 

 ersed in its whole length by two parallel, strong, secondary nerves, appar- 

 ently vanishing below the top (broken). Except very few oblique curved 

 tertiary veins, no other trace of nervation or areolation is distinct. The 

 medial nerve from under the sinus downward is 3 millimeters broad — as 

 broad as the short pedicel broken 2 centimeters below the slightly decur- 

 rent base of the leaf. 



Hob. — Near Morrison, Colorado. H. C. Beckwith. Found only in one 

 good specimen. 



Liriophyllum populoides, Lesqx. 

 Plate XI, Figs. 1 and 2. 



Leaves smaller, broadly ovate, cuneiform at base, divided nearly vertically from 

 the top to above the middle into two obtuse lobes, enlarged on the rounded sides above 

 the base and there sometimes prolonged iuto a short obtuse lobe; medial nerve straight; 

 lateral nerves strong, parallel, equidistant, four pairs, effaced near the borders, rarely 

 branching; nervilles at right angles. 



In comparing these leaves with the preceding the essential characters 

 are seen to be identical, though the appearance is far different. The large 

 size of the leaf and the subdivision of the two primary lobes in L. Beck- 

 ivithii are the more marked differences. But in fig. 1 of this species the 

 lower side is continued into a short lobe, indicating a subdivision like that 

 of the leaf pi. x, fig. 1, and the nervation is of the same type as in the leaf 



