FLORA OF THE SHASTA FORMATION. 257 



Geyser specimens show that these shorter and broader leaflets may be 

 found on the lower portions of leaves which, higher up, have longer and 

 narrower leaflets that are of the typical form of Z. arcticus. 



Zamites tenuineevis Fontaine. 



PI. LXVIII, Figs. 2, 3. 



1889. Zamites tenuinervis Font.: Potomac Flora (Monogr. U. S. Geol. Surv., Vol. 

 XV), p. 171, pi. Ixvii, fig. 1; pi. Ixix, fig. 2; pi. Ixx, fig. 1; pi. Ixxv, fig. 3; 

 pi. Ixxvi, fig. 7; pi. Ixxviii, fig. 6; pi. Ixxxiv, fig. 7. 



At locahties Nos. 1, 9, 12, 18, 19, 20, and 22 a number of fragments 

 occur that strongly suggest identity with Zamites tenuinervis Font., 

 one of the most common cycads of the Lower Potomac of Virginia. 

 At locality No. 23 a good specimen was found, that given in PI. LXVIII, 

 Fig. 2. This shows the basal portion of a detached leaflet, with a good 

 deal of the remainder, but the tip is wanting. All the characteristics 

 of Z. tenuinervis except the auriculate base are shown in this specimen, 

 and there is no doubt that it is identical with the Potomac fossil. Some 

 of the supposed fragments of this plant, found elsewhere, have a decep- 

 tive appearance of strong nerves, which is caused by stripes of car- 

 bonaceous matter that adhere to some of the nerves throughout their 

 length. The specimen shown in PI. LXVIII, Fig. 3, is from localitv 

 No. 12. 



Genus CYCADEOSPERMITM Saporta. 



CYCADEOSPEEMtTM CALiFORNicuM Fontaine n. sp. 



PI. LXVIII, Fig. 4. 



A single specimen of a nut-like seed was found at locahty No. 19. 

 It seems to have been of a hard consistency, with a smooth surface. 

 It stands out prominently from the rock. It is ovate-elliptical in form, 

 2 mm. wide in the widest portion, and 7 mm. long. It tapers to an 

 acute point and has obscure striae on its surface, which can be seen 

 only with a lens. It seems to be a new species, but this may not be the 

 case, as seeds of this nature do not usually have points of character 

 sufficient positively to determine their true position. This is the only 

 seed thus far found in these collections of fossils from the Shasta group. 



MON XLTUI — 05 17 



