232 THE POTOMAC OR YOUNGER MESOZOIC FLORA.. 



Seed of Leptostrobus ? (c), sp.? 



Plate CXXXVI, Fig. 11. 



Seed oblong-elliptical, with a slight acute tip at one end and a very 

 short stem-like prolongation at the other. Smooth, winged ; wing very 

 large in proportion to the seed, widest in the middle and flared out there, 

 narrowed towards the apex and base, prolonged to a short subacute point, 

 and ending below in what seems to be a point of attachment to a pedicel. 



Locality: Kankey's; only one specimen found. 



This seed differs from the others in its greater size as well as that of 

 the vving, and in the greater proportional size of the wing as compared 

 with the seed, also in the flaring out of the wing in its middle portion. It 

 is a little like Heer's Samaropsis rotimdata. It is possible that these seed 

 do not belong to Leptostrobus, but to the genus next to be described, viz, 

 Laricopsis, for Larix has samara-like seed. 



LARICOPSIS, gen. nov. 



Trees or shrubs, with the penultimate twigs sending off alternately in 

 the same plane ultimate branches ; leaves thin, narrow, and thread-like, 

 attached by the entire base either in bundles at the same point on the 

 stem or scattered singly on its surface, both on the same stem, very 

 deciduous, the leaf-bundles leaving small scars Nerves not made out 

 with certainty, but apparently one for each leaf 



This genus is nearer to Larix than to any other known plant, and the 

 resemblance is sufficiently great to render it possible that it may be the 

 ancestor of this genus. It should be noted that the young shoots of Larix 

 often have the leaves scattered singly as they occur in this genus, and it is 

 probable that the immature portions of Larix approach the ancestral forms 

 more nearly than the mature portions do. In these specimens also the 

 leaves appear most often to be attached laterally to the stems as now pre- 

 served, while no doubt they were originally scattered around the stem. 

 This appearance, as in the case of Leptostrobus, is doubtless due to the 

 accidents of preservation. No nerves could be made out with certainty. 

 The leaves are very narrow, being sometimes like hairs. 



