FOSSIL FLORA. 741 



YITACEiE. 



Cissus haguei n. sp. 

 PL CI, fig. 2. 



Leaf membranaceous, quadrangular-ovate, truncate or possibly slightly 

 heart-shaped at base and acuminate at apex, lateral lobes short, obtuse; 

 margin toothed, the teeth low, obtuse or somewhat acute; nervation 

 palmate, midrib thin, perfectly straight, lateral ribs of same strength as 

 midrib, arising at an angle of 45°, passing directly to and terminating 

 in the obtuse lateral lobes; ribs with 4 or 5 branches on the outside, 

 which terminate in marginal teeth; secondaries about 4 pairs, alternate, 

 at same angle as the ribs and terminating in the teeth; nervilles thin, 

 sparse, percurrent or often broken. 



This fine leaf is 8.5 cm. long, 5.2 cm. broad between the lobes and 6.5 

 cm. broad in the widest part, which is only a short distance above the base. 

 In outline it is what may be called quadrangular-ovate — that is, between 

 ovate and square. It is palmately 3-ribbed, the lateral ribs being at an 

 angle of about 45° and of the same strength as the midrib. They pass 

 straight to and terminate in the short lateral lobes, and have 4 or 5 out- 

 side branches which also terminate in the marginal teeth. 



The relation of this species is undoubtedly with Cissus parroticefolia 

 Lx., 1 from the Green River group. This latter species differs in being 

 relatively longer, without especially marked lateral lobes, with larger, more 

 obtuse teeth, and unforked outer branches of the lateral ribs. There are 

 also more secondaries in the upper part of the leaf. These, however, are 

 but slight differences, and are possibly only such as might be expected in 

 individual variation. But as only one example has been found in the 

 Yellowstone National Park, there is no means of knowing what maybe 

 allowed for individual variation, so I have preferred to keep them separate. 



I take pleasure in naming this species in honor of Mr. Arnold Hague, 

 who collected it. 



Habitat: Fossil Forest Ridge, middle .stratum; collected by Arnold 

 Hague, September 24, 1884. 



'Tert. Fl., )>. 239, PI. XLII, fig. 1. 



