OLDEK roru.MAC: OF VIUUIMA AM) .MAKYLAM). 537 



These fossils alone would not suffice to fix the ajjje of the rocks 

 yieklinfi them, hut do not oj)pose the assumption of the Ariuulel or 

 Rappahannock age of the material. 



KOSMI, I'l.AMS UtOM ((IMKK. , 



[PI. J.XXX, Nos. 95, U7.] 



Two specimens come from near Contee, which is the next station 

 northeast of Muirkii'k, on the Baltimore and (Jhio Raih'oad. The label 

 accompanying one of these reads: "Peterson's mine, near Contee, 

 Prince George Co., Md." (PI. LXXX, No. 1)7), with no formation 

 named. The fossil is a clay cast of a small cone which probably belongs 

 to AlhniNn-opsif; cxjxinsa Font. It suggests that the age of the forma- 

 tion is Arundel, or, what is the same thing, Rappahannock. It is Xo. 

 8242 of the Maryland Geological Survey, collected by Mr. Bil)l)ins in 1S96. 



The other is a specimen of Cycadeospcrmum rofu)i<latu)tt Font., 

 credited on the label accompanying it to ''Iron-ore clays, B. & O. R. R. 

 cut, Contee, Maryland" (PI. LXXX, Xo. 95). This species in the Vir- 

 ginia Lower Potomac" was found in only one specimen, in strata of 

 Rappahannock age. So far as its evidence goes, it indicates that the 

 clays yielding it belong to the Arundel. The label does not give date 

 or collector, but it is marked "M. G. S., 8779." 



FOSSn, I'LAXTS FROM ARl.IXnoN. 



[PI. LXXX, No. 73.] 



This locality is half a mile north of the village of Arlington and a 

 mile and a half east of Jessup station on the Baltimore and Ohio Railroad, 

 on the high ground, nearly 300 feet above sea level, which forms the 

 divide between the Patuxent and Patapsco drainages, through which 

 passes the somewhat famous Jessup Cut. Several large collections were 

 made by Mr. Bibbins from points only a short distance apart in this 

 general region (see p. 389). These collections contain more specimens 

 than were obtained from any other locality. They are, however, mostly 

 duplicates of a comparatively small numbei- of species. As the species 

 show that the various localities belong to the same horizon, and as the 

 rock matter containing them indicates that they come from the same 



'Monograph XV, p. 271, pi. cxx.wi, fif;. 12. 



