OLDER POTOMAC OF VUUilMA AND MARYLAND. 483 



WiLiJAMSoxiA? (;ai,i,inacf.A Ward n. sp." 



PI. evil. V\'^. A. 



Tlie supiM)secl WillianisoniM is a fragment , showing what seems to he 

 the summit of tlie peduncle of the infioi-escence, with portions of the Ijases 

 of the bracts. It is not distinct enough to make the generic identification 



positive. 



The Ust given above of the plants obtained from Cockpit Point shows 

 that the horizon is tliat of the Rappahannock or iMcckMicksbui'g beds; 

 that is, near the base of the lower Potomac, corresponding to Professor 

 Ward's Rappahannock series. This is confirmed by the character of the 

 strata, for the fossiliferous stratum is, in lithological character, nuich like 

 the basal material of the lower Potomac found at Alum Rock, near the 

 town of Fredericksburg. It rests on unlaminated, greenisli, sandy 

 material which weathei's bright red. This rock matter is charactei-istic of 

 the l)ottom beds of the lower Potomac in the northern portion of the 

 formation in Virginia. 



KOSSIh I'l.AXTS KKOM NKAK H ((OIHtlUIXiK. 



Cycadeospermum obovatttm Fontaine. 

 PI. CVII, Fig. 5. 



1889. Cycadeospennum ohovatum Font.: Potomac Flora (Monogr. U. S. Geol. Surv., 

 Vol. XV), p. 270, pi. cxxxv, fig. 13. 

 Mr. Victor Louis Mason obtained on October 5, 1893, a complete 

 seed of Cycadeospermum ohovatum Font, from a cut on the Atlantic 

 Coast Line Railroad below (south of) Woodljridge, Va., near the north 

 end of the cut. This is from the same horizon as the plants from near 

 Lorton, next to be considered. It occurs near the contact with the 

 Cambrian slates. In Monograph XV these slates were spoken of as 

 Azoic, but later investigations show them to be prolxalDly Lower 

 Cambrian. 



KOSSll. I'l.V.NTS KKOll \KAR l.dliTttN STATION. 



This is the locality formerly known as "Telegraph Station." It 

 was designated ])y this latter name in Monograph XV, j). 22. The 

 railroad station is at Springman post-office. The spot from which the 



" Professor Kontaino a.ssigned no specific name to this form. The niinie adopted alhides to tlie locality.— 

 L. F. W. 



