146 



MOLLUSCA. 



No. 679. Trigonia costata, Park. 



This and the next three forms belong to the Trigoniadce, 

 the shell of which is equivalve and trigonal, with the uni- 

 bones directed posteriorly. From the Lower Oolite, (Esch- 

 ingen, Wirtemberg, and now in the Ward Museum, Uni- 

 versity of Rochester. Price, $0.40. 



No. 680. Trigonia clavellata, Sow. 



From the Oxford Clay (Middle Oolite), Dives, France, and now in the pri- 

 vate Geological Cabinet of Mr. Ward, Rochester. Price, $0.75. 



No. 681. Trigonia candata, Agass. 



A species with high smooth ribs, from the Lower Greensand of the Isle of 

 Wight, England, and now in the private Geological Cabinet of Mr. Ward, Roch- 

 ester. Price, $0.40. 



No. 682. Trigonia crenulata, Lam. 



From the Lower Chalk of Rouen, France, and now in the Ward Museum of 

 the University of Rochester. Price, $0.35. 



No. 683. Modiola plicata, Sow. 



This and the two following are " Mussels" {MytiUdee), having an elongated, 

 equivalve shell, with anterior umbones, edentulous hinge, and two muscular im- 

 pressions. These two specimens (on pedestal) of M. plicata are from the Lower 

 Oohte, Rendcomb, England, and are now in the Ward Museum, University of 

 Rochester, Size, 6x4. Price, $0.80. 



No. 684. Orthonota undnlata, Conrad. 



From the Hamilton group (Devonian), Summit, Schoharie Co., New York. 



Price, $0.30. 



No. 685. Congeria ( Dreissena ) subglobosa, Partsch. 



This is a very characteristic, globose and finely 

 modelled form of bivalve shell. It abounds in the 

 " Tegel," or sandy loam (MioceneTertiary) of Brunn, 

 Austria, and now in the Ward Museum, in the Uni- 

 versity of Rochester. Price, $0.50. 



No. 686. Thracia . 



This and the following belong to the Anatinida. This species is from 

 the Cretaceous of Egypt, and is now in the Ward Museum, University of 

 Rochester. Price, $0.50. 



No. 6S7. G-rammysia Hamiltonensis, Vemeuil. 



From the Hamilton Group (Devonian), Cazenovia, N. Y. 



Price, $0.30- 



