28 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



tula, hardly mixed with any other species, and containing, so far as 

 could be discovered, no perfect specimens or lower valves. 



Stratum A^ is regarded by Mr. Hemphill as the outcropping of an 

 extensive formation probably underlying the whole of the level land 

 back to the bluffs, and presenting estuarine characters. It is sur- 

 mounted by, or passes into, a fine sandy deposit (B^), at least seventy 

 feet thick in some places, containing fossils scattered through it, and it 

 is in this stratum that the fossils from the well were found. In nearly 

 all the wells that have been sunk in San Diego, fossils have been found, 

 showing that the bed is of wide extent as well as of great thickness. 



Tlie following fossils were afforded by stratum A^ : — 



Cardium procerum. 

 Ostrea lurida. 

 Anomia Umatula. 



Pholadidea ovoidea. 

 Solecurtus californianus. 

 Macoma sabulosa f 

 Tell'ma Bodegensis. 

 Donax Jlexuosu.s. 

 Mactra falcata. 

 CAementia suhdiaphana. 

 Ghione shniUhna. 

 Chione succincta. 

 Dosinia ponderosa. 

 Saxidomus aratus jun. 

 Petricola pkoladiformis f 



FissurelUdea callomarginata. 

 Crucibulum sjnnosuni. 

 Cerithidea sacrata. 

 Drillia peniciUata. 

 Scalaria indlanorum. 

 Ranella muriciformis. 

 Nassa fossata. 

 Nassa tegula. 

 Cerostonia Nnttallii. 



From tbc well-digging in stratum W came. 



Venericardia monilicosta. 

 Area microdonta. 

 Leda coelata. 

 Pecten expansus. 

 Janira dentata. 

 Mamma nana. 



Crepidula princeps. 

 'TurriteUa Coopcri. 

 Turbonilla stylina. 

 J^assa mendica. 

 Cyliclma alba. 

 Cadulus fusifonnis. 



To which may be added the following species not enumerated from that 

 locality in the list (pp. 11-12) in these Proceedings, but also obtained by 

 Mr. Hempljill: — 



Glottidia alhUla Hds. 

 Xylotrya sp. (tubes). 

 Gryptomya californica Cour. 

 k^olen rosaceus Cpr. 

 Solecurtiis californiatms Conr. 

 Macoma expansa Cpr. 

 dementia suhdiaphana Cpr. 

 Cardium centifilosum Cpr. 

 Liicina N'uttallii Conr. 

 Lucina acutiUneata Conr. 



Lucina temiisculpta Cpr. 

 Cryptodon Jlexuosiis Mont. 

 Modiola recta Conr. 

 Nucula exigua Sby. 

 Acila Lyallii Bd. 

 Pecten liastatus Sby. 

 Janira jlorida Hds. 

 Ostrea conchaphila Cpr. 

 Placunanomia macroschisma Desh. 

 Tornatina eximia Bd. 



