78 



PHYSIOGRAPHY AND GEOLOGY OF THE COASTAL PLAI^! PROVINCE. 



V. Section at Howlett House Bluff. 



Peet 



Pleistocene. Sunderland Yellowish sandy loam about 45 



Miocene. Calvert Fine yellow sand clay. about 35 



Kocene. Aquia Glauconitic argillaceous sand becoming indu- 

 rated below 15 



Lower Cretaceous. Patuxenf Coarse gravelly sand 10 



Cross-bedded, arkosic sand 18 



Similar materials with cobbles. Indurated in 

 places 2 



Total .' 125 



Between this point and the lower entrance to the canal clay lenses of 

 very limited extent, and clay balls, have furnished the following fossil 

 plants : 



Acrostichopteris parvifolia Font. Dioonitcs Buchianus (Ett.) Born. 



Acrostichopteris pluripartita { Font. ) Frenelopsis parceramosa Font. 



Berry Onychiopsis Goepperti (Schenck) Berry 



Araucaria obtusifolia Font. Ruffordia (loepperti (Dunk.) Seward. 



Araucarites virgini&us Font. Hphenolepis Kurriana (Dunk.) Schenk 



Brachyphyllum. ci~assicaule Font. Thyrsopieris angufitifolia Font. 



CJadophlehis Albertsii (Dunk.) Brongn. Thyrsopteris angustiloba Font. 



Cladophlebis Browniana (Dunk.) Seward. Thyrsopteris rarinervis Font. 



Cladophlebis Ungeri (Dunk.) Ward ^Villiamsonia virginiensis Font. 



The next and last exposure of Potomac Group on the James Elver is at 

 Deep Bottom, 4 miles below Dutch Gap on the left bank just below 

 Three Mile Creek. At thi's point the following section is seen in the ravine 

 of the creek. 



VI. Section at Deep Bottom.. 



Feet 



Pleistocene Argillaceous sand and loam 10-20 



Gravel bed 6-10 



Eocene Glauconitic argillaceous sand 4-6 



Lower Cretaceous. Patapsco Exposed about 3 



Arkosic sand with cobbles above and containing 

 lenses and balls of sandy brownish clay carry- 

 ing leaf impressions including Araliaephyl- 

 lum crassinerve (Font.) Berry, Cladophlebis 

 constricta Font., Ficophyllv/m crassinerve 

 Font., Juglandiphyllum integrifolium Font., 

 Nageiopsis longifolia Font., Podozamites acu- 

 tif alius Font.,, Populophyllum crassinerve 

 Font., Sapindopsis magnifolia Font., Sassa- 

 fras bilobata Font., Sphenopteris latiloba 

 Font., StercuUa elegans Font., Thyrsopteris 

 brevipennis Font., and Ulmiphyllum crassi- 

 nerve Font 



Total 22-38 



