22 G. D. Harris — Tertiary Geology of Maryland. 



No. 1. Light yellowish sand 5 feet. 



2. Light clay, brownish above... . 5 " 



3. Isocardia layer 2 inches. 



4. Bluish clay with Lucina subplanata 2 feet. 



5. Ostrea percrassa bed, greenish sand 6 inches. 



6. Bluish sandy clay 2 feet. 



The beds here represented dip slightly to the north. They 

 are cat off by Pleistocene deposits before reaching half way to 

 Fishing creek, so that it is impossible to determine how far 

 northward this abnormal dip extends. 



Section 3. — This is the locality described by Conrad as 

 " Colonel Blake's " in the Second Bulletin of the Proceedings 

 of the National Institution, page 181. He says : " The cliff is 

 at least one hundred and fifty feet high. At base we found a 

 clay replete with a species of Tellina, probably new, and over 

 this at about six feet elevation, a thin stratum of Ostrea per- 

 crassa. The upper portion of the cliff consists of sand and 

 clay, and appears to be destitute of organic remains." 



Conrad doubtless examined this locality somewhat hastily, 

 insomuch as several fossiliferous beds occur in the sand and 

 clay regarded by him as " destitute of organic remains." 



The section stands thus : 



No. 1. Light colored clayey sand 25 feet. 



2. Sandstone ferruginous layer. (Fossiliferous ?) 4 " 



3. Blue clay 10 " 



• 4. Ferruginous sand. (Fossiliferous?) 3 " 



5. Blue clay 20 " 



6. Zoned; Isocardia bed ; ferruginous sand 5 " 



7. Bluish sandy clay 15 " 



8. Ferruginous brownish sand 4 " 



9. Blue clay.. 8 " 



10. Zone b / greenish gray fossiliferous sand. 



This stratum is overlaid by a line of .con- 

 cretions 12 " 



11. Light bluish sandy clay ; Corbula layer 3 



feet from base 18 " 



12. Zone a; Ostrea percrassa, in greenish sand.. 6 inches. 



13. Gray sandy clay to surface of water 6-8 feet. 



From Zone b, at this locality, Mr. Burns and the writer ob- 

 tained the following species : 



Pelecypoda, — Pecten madisouius, Area subrostrata, Pectunculus 

 parilis, Nucula sp. undt., Astarte varians, Crassatella melina, 

 Lucina anodonta, Lucina Foremani, Lucina crenulata, Cardium 

 leptopleura, Isocardia Markoei, Venus latilirata, Venus staminea, 

 Cytherea marylandica var. ?, Tellina subreflexa, Corbula idonea, 

 Corbula elevata, Panopsea porrecta ? 



