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 2 is regarded by Mr. Hemphill as the outcropping of an 

 extensive forma tion, 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 2 ), 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. 



The following fossils were afforded by stratum A 2 : — 



Pholadidea ovoidea, 

 Solecurtus calif or nianus. 

 Macoma sabulosa f 



Tellina Bodegensis. 

 Donax jlexuosus. 

 Mactra falcata. 

 Clementia subdiaphana. 

 Chione simillima, 

 Chione succincta. 

 Dosinia ponderosa. 

 Saxidomus aratus jun. 

 Petricola pholadiformis f 



Cardium procerum. 

 Ostrea lurida. 

 Anomia Mmatula. 

 Fissurellidea callomarginata. 

 Crucibulum spinosum. 

 Cerithidea sacrata. 

 Drillia penicillata. 

 Scalaria indianorum. 

 Eanella muriciformis. 

 Nassa fossata. 

 Nassa tegula. 

 Cerostoma Nuttallii. 



From the well-digging in stratum B 2 came, — 



Venericardia monilicosta. 

 Area microdonta. 

 Leda coelata. 

 Pecten expansus. 

 Janira dentata. 

 Mamma nana. 



Crepidula princeps. 

 Turritella Cooperi. 

 Turbonilla stylina. 

 Nassa mendica. 

 Cyliclina alba. 

 Cadulus fusiformis. 



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. Hemphill: — 



Glottidia albida Hds. 

 Xylotrya sp. (tubes). 

 Cryptomya californica Conr. 

 Solen rosaceus Cpr. 

 Solecurtus californianus Conr. 

 Macoma expansa Cpr. 

 dementia subdiaphana Cpr. 

 Cardium centifilosum Cpr. 

 Lucina Nuttallii Conr. 

 Lucina acutilineata Conr. 



Lucina tenuisculpta Cpr. 

 Cryptodon Jlexuosus Mont. 

 Modiola recta Conr. 

 Nucula exigua Sby. 

 Acila Lyallii Bd. 

 Pecten hastatus Sby. 

 Janira florida Hds. 

 Ostrea conchaphila Cpr. 

 Placunanomia macroschisma Desh. 

 Tornatina eximia Bd. 



