DESCRIPTION OF SPECIES— NELUMBOXiE. 253 



one side; none of them eitlicr has (iichotomous divisions, and thus the leaves 

 of this species seem far ditTcrcnt from those of our time, as also from those 

 described from the European Tertiary. Li the small leaves of N. lutcum, 

 the nerves, twice as numerous as in this species, have also a tendency to turn 

 on each side toward the midrib; tliis character is not remarkc<l upon the frag- 

 ments of figs. 1 and 2, thougli it is distinctly so in the better preserved leaf 

 of lig. ;>, which T consider as a different species. 



Habitat. — Golden, Colorado {Rev. Arthur Lakes). 



IV e I u III b ■ u m t e ii u i f o I i u in , Lesqz. 

 Plate XLVI, Fig. 3. 



Jfelumhium tenuifoHam, Lesqs., Auuual Report, 1873, p. 402. 



Leaves of a thin texture, couiparatively small, eight to nine centimeters in diameter, orbicular, 

 peltate from the miiUlIe, with flat, undul.ate borders ; primary nerves thin, equal aud equidistant, curved, 

 simple or sparingly branching, crossed at right angle by nervilles, craspedodrome. 



The essential differences between this and the former species consist in 

 the thin substance of the tissue of the leaves, the narrower veins, the borders 

 flat, not recurved, the surface smooth or not roughened Ijy the nervation. 

 The number of the nerves, thirteen, instead of fourteen, cannot be considered 

 as of any marked importance. In all the species, either living or fossil, known 

 until now, the primary nerves are dichotomous in their division, a character 

 at variance with that o<'the nervation of the former species, and which might 

 su"-o-est some doubt in regard to the relation of these leaves to Nelumhium. 

 As we do not have in Europe any species of this genus from the Eocene 

 period, we may have here the earliest representative of a new type, whose 

 leaves may not have as yet reached their full development. But even m 

 this fig. 3, we see either simple nerves, or a few branches diverging from the 

 midrib, as in the common nervation of the dicotyledonous leaves, or dividing 

 at the top by an exact dichotomous division, as seen by two of these nerves. 

 Moreover, we have here, on the left side, a straight nerve like a midrib, toward 

 which the lateral veins curve, or rather a back nerve, as in N. luteum, m right 

 line with the midrib to the point of which the lateral veins take their direc- 

 tion. In our living species, the two nearest nerves to this back vein often 

 curve, and reach its point by their ends. I do not think, therefore, that the 

 reference of these leaves to Nelumhium is contestable. In regard to the 

 possible identity of these three leaves, it could scarcely be admitted. The 

 great difference in their substance seems siiflicient to authorize a separate 

 specification, though, in the exaniintition of numerous leaves of N. luteum, 



