Mesozoic and Ccenozot'c Geology and Paloi ontology. 275 



ascending order, into : 1. Cluiborne group, characterized by Cardita 

 densata^ Ostrea selliformis, Crassatella alta^ Pectunculus stamineus, 

 Meretrix oequorea, Gratelupiahydi, Ledacoelata, and Crepidula lirata. 

 2. Jackson group, characterized by Umbrella planidata^ Cardium 

 nicollettii, Conus tortillis, CyproBa fenestralis^ Galeodia j^eteisoni, a,nd 

 Rostellaria extenta. 3. St. Stephen's group, characterized by Pecten 

 poulsoni, and OrhituUies mantelU. 4. Vicksburg group, characterized 

 by Corhula alfa, Crassatella mississippiensts, Area mississippiensis, 

 Meretrix sohrina. 3f. imitabilis, and Turbinella wilsoni. He described,* 

 from Jackson, Miss., nnd Claiborne, Ala., Endopachys expansum^ E- 

 triangulares E. alcicostaturn, Elabellimi wailesi, Osteodes irroratus, 

 Tarbinolia lunulitiformis. Chiton antiquus, C. eocenensis ; and from 

 White river, Arkansas, Petrophyllia arkansasensis; froni the Miocene, 

 of Colorado and the West, Anomia subcostata, Ifei^cenaria perlami- 

 nosa, Pecten heermani, Pandora bilirata, Astarte thomasi, Turritella 

 secta, Ostrea contracta, and Tdraonea calif ornica. 



Prof. VV^m. P. Blake noticed Miocene strata, containing the remains 

 of Infusoria and Polythalamia, near Monterey, California. The strata 

 are white, porous, light, resemble chalk, and are situated about two 

 miles southeast from the center of Montere}-, and form part of a hill 

 which fronts the ba_y, and rises on the east side of the stage-road to San 

 Francisco to the height of 500 or 600 feet. 



Tuome}" and Holmesf described, from the Pliocene of South Carolina, 

 Cellepora formosa, G. depressa, C. radiata, C. tessellata, Ilembrani- 

 pora lacinia, Placunanomia plicata., Ostrea ravenelana, Janira 

 affinis, Pecten coynparilis, P. peedeensis^ Mytiliis injlatus. Area Mans, 

 A. rustica, Pectunculus loivis, Lucina cosf.ata, Crassatella gibbesi, 

 Psammocola pliocena, Dentalium pliocenum, Hipponix bulli, Mono- 

 donta Mawahensis, Trochus armillatus^ T. gemma, Terebellum stria- 

 tum, T. burdeni, T. etiwanensis^ Voluta trenholmi, Porcellana olivi- 

 formis. Purpura tridentata, Cancellaria depressa, C. venusta^ Busycon 

 Gonradi, Cassidulus carolinensis, and Fasciolaria tuomeyi. 



J. McCrady described, from the same strata, Psammechinus exoletus, 

 Agassizia porifera, Amphidetus amplijlorus, A. gothicus, Brissus 

 spatiosus, Plagionotus holmesi, and P. ravenelanus. 



Dr. Trask;^ described, from the Pliocene of Santa Barbara, California, 

 Chemnitzia papulosa s Tornatella elliptica, Murex fragilis, Fusus bar- 

 barensis, F. robustus, ^and F. rugosus. 



* Proe. Acad. Nat. Sci., vol. vii. 



t Tuomey and Holmes' Fossils of South Carolina. 



X Proc. Cal. Acad. Sci., vol. i. 



