182 
PROCEEDINGS OF 
Univalves. Univalves. 
.Fissurella marylandica, Conrad. Trochus peralveatus, Conrad. 
Voluta mutabilis, Conrad. Turritella indenta, Conrad. 
Infundibulum perarmatum, Conrad. Turritella exaltata, Conrad. 
Marginella perexigua, Conrad. Turritella perlaqueata, Conrad. 
Pleurotoma marylandica, Voluta solitaria. 
Following the coast three or four miles south, we observed another vertical cliff, 
about thirty-five feet in elevation, near Captain Beckett’s. The fossils can be traced 
nearly to the last mentioned locality. At base is a brown mixture of sand and clay, 
with the same group of shells above mentioned, wliich are very numerous in a bed 
four feet in thickness. Specimens are difficult to obtain in quantity, as they must 
be procured in a low cavern hollowed out by the waves. In the next three feet, the 
same fossils occur, less abundantly; then succeeds twenty feet of mingled sand and 
clay apparently destitute of fossils. Above, and resting on this, is a stratum about 
three feet thick, of quartzose sand, very incoherent and filled with shells, among 
which I recognised Artemis acetabulum, Orbicula lugubris, and Pecten Madiso- 
nius; but the bed being inaccessible without a ladder, the amount of species could 
not be ascertained. 
Cliff near Beckett’s. 
Ft. in thickness. 
5 
Sand, without shells. 
3 
Sand, with innumerable shells. 
20 
Mingled sand and clay, without fossils, or very rare. 
3 
Same as below, less numerous. 
4 
Sand and clay, with a group of shells like that at Hance’s. 
The fossilliferous cliffs of the medial tertiary period extend from here to the 
mouth of Patuxent river. 
Through the kind attentions of Dr. James and Dr. G. Granger Tongue, we were 
enabled to make some interesting excursions in the lower part of Calvert county; 
but I regret our limited time allowed us only a rapid glance at the long line of coast, 
both on the Chesapeake and Patuxent, so replete with interest to the geologist, 
and so rich in organic remains. Commencing near the southern extremity of Cal¬ 
vert, we coasted the Chesapeake, in front of the usual mural escarpment which 
characterizes the tertiary cliffs of this region, and which continues to the vicinity of 
Cove Point, where the land slopes gradually to the beach. At the point where we 
commenced observation, vast quantities of the Turritella plebeia, the common spe¬ 
cies of St, Mary’s river, appear in veins or thin beds, in clay, just above the level 
