DESCRIPTION OF SPECIES— LONICERBiE. 225 



Viburniiiii rotundif o liu ni, Lesqz. 

 P'ate XXXVII, Fig. 12; Plate XXXVIII, Fig. 10; Plate LXI, Fig. 22. 



Vihurnum rot undifoJium, Lesqx., Annual Report, 1874, p. 305. 



Leaves small, nearly round, surrounded by a black border, dentate, ronnded-subcordate at the 

 base; nervation thin, caniptodrome. 



Except that the leaves are all small, nearly round, subcordate or truncate 

 at llie base, and the nerves thin, the characters of these leaves are the same 

 as those of V. marginatum. They are generally unequal at the base, and the 

 basilar secondary veins emerge from the top of the petiole; the teeth are, 

 comparatively to the size of the leaves, quite as distinctly marked as in the 

 former species. Saporta considers this and the following as referable either 

 to F. marginatum or to V. platanoides. 



Habitat. — Black Buttes, Wyoming, where it is rare ; Point of Rocks, 

 Wyoming {Dr. F. V. Hayden). 



Tiburnuin dicliotoniiim, Lesqx. 



Plate XXXVIII, Fig. C. 

 Viburnum dichotomum, Leeqx., Annual Report, 1872, p. :i99. — Schp., Pal. V^g^t., iii, p. 601. 



Leaf subcoriaceous, oval, obtuse, ronnded to the petiole; borders dentate; secondary nerves 

 alternate. 



The consistence of this leaf is somewhat thicker than that of the above- 

 described congeners. The distribution of the secondary veins is quite differ- 

 ent, as they come out alternately, and are like dichotomous divisions from a 

 series of flexures of the midrib. Except this, there is no marked difference 

 in the nervation. The oval form of the leaf, rounded at the base, is also 

 peculiar to this leaf, which may be a variety of V. marginatum. Its borders, 

 however, are not black-margined, and the surface is smooth. It closely 

 resembles, by its characters, V. eUij)ticum, Hook., of Oregon. 



Habitat. — Black Buttes, Wyoming, baked shale. 



Tiburnuin 'Whyniperii, Heer. 



Plate XXXVIII, Fig. 7 ; Plate LXI, Fig. 23. 



Viburnum Whymperi, Heer, Fl. Foss. Arct., ii, p. 475, pi. xlvi, fig. 1 ; Spitz. Fl., p. 60, pi. xiii, tigs. 3-23. — 

 Lesqx., Annual Report, 1872, p. 395. 



Leaf oblong, obtuse, or subtruncate, rounded to the base ; borders denticulate ; secondary veins 

 thin, numerous, irregularly divided, craspedodrome. 



This reference is doubtful. These leaves differ esjjecially from those 

 of the former species by the more numerous, close, smaller teeth, and by 



15 T F 



