506 MESOZOIC FLORAS OF UNITED STATES. 



Leptosteobus longifolius Fontaine. 



PI. CX, Fig. 11. 



1889. Leptostrolus longifolius Font.: Potomac Flora (Monogr. U. S. Geol. Surv., 

 Vol. XV), p. 228, pi. ci, figs. 2, .3: pi. cii, figs. 1-4; pi. ciii, figs. 6, 6a-6e, 

 7, 8, 8a, 9-12; pi. civ, fig. 6. 



In the collection occurs one specimen of Leptostrobus longifolius 

 which shows leaves attached to a portion of a stem. These show a 

 peculiar broadening at the base, where attached, which is probably 

 due to distortion from pressure. PL CX, Fig. 11, is given to show this. 

 The impression occurs on the rock specimen, No. 8431, with other species. 



Onychiopsis PSiLOTOiDES (Stokes & Webb) Ward." 

 PI. CXI, Fig. 4. 



This plant is of much importance in this collection. PL CXI, 

 Fig. 4, gives the best of the three specimens found. It is a portion 

 of a penultimate pinna with a number of ultimate ones, carrying well- 

 characterized pinnules. The imprints are all on a single slab in coun- 

 terparts, the part bearing the one figured l^eing No. 8428 and the 

 counterpart No. 8430 of the Maryland Geological vSurvey. 



This fern is more characteristic of the Rappahannock than of the 

 Aquia Creek horizon. 



Sassafras bilobatum Fontaine.? 



PI. CXI, Fig. 5. 



1889. Sassafras bihhatmn Font.: Potomac Flora (Monogr. U. S. Geol. Surv., Vol. 

 XV), p. 290, pi. clvi, fig. 12; pi. clxiv, fig. 4. 



There is in the collection a fragment of a leaf of considerable size 

 which is of problematic character but which in some points resembles 

 Sassaf7^as bilobatum from the Aquia Creek horizon of the Virginia Lower 

 Potomac. It is, however, too poorly preserved to permit its true char- 

 acter to be made out. It is most like the form given in Monograph XV, 

 pi. clxiv, fig. 4, but the fragment indicates a leaf larger than the one 



"For s3'nonymy of this species see pp. 155-156.. 



