MIOCENE MOLLUSCA AND CEUSTACEA. 73 



This feature, with its extreme ventricose form, broad incurved postero-car- 

 dinal area and large distinctly marked lunule, are features which will sep- 

 arate it very readily from any other shell in the Miocene deposits. 



Locality: The New Jersey specimens, which are very young shells, are 

 from near Shiloh, N. J,, and belong, one to the State collection at New 

 Brunswick and the other to the National Museum. The large South Caro- 

 lina specimen is in the American Museum of Natural History, New York 

 City, and from the Holmes collection, but not marked with locality. 



Genus DOSINIA Scopoli. 



DOSINIA ACETABULUM. 



Plate xiii, fig. 2. 



Artemis acetabulum Conrad: Foss. Shells Tert. Form., p. 20, PL vi, fig. 1; Miocene 

 Foss., p. 29, PL xvi, fig. 1; Heilprin: Proc. A. N.S., Phil. 1887, pp. 401 and 103. 



Dosinia acetabulum Conrad: Proc. Acad. Nat. Sci. Phil. 1862, p. 575; Meek, Check 

 List Miocene Foss., p. 10. 



"Lentiform, with numerous concentric striae, which are rather sharp 

 and elevated on the anterior and posterior sides; cardinal fosset large, 

 oblong, profound; with age, almost obliterating the posterior tooth; right 

 valve with three teeth, the posterior one- long and sulcated longitudinally; 

 two anterior teeth approximate; left valve with four teeth, three of them 

 distant; the anterior tooth somewhat pyramidal and entering a groove 

 formed by two slight elevations in the opposite valve." (Conrad in Mio- 

 cene Foss.) 



I have seen only a few fragments of this species, but of very charac- 

 teristic features. They come from the well-boring at Atlantic City, and 

 represent three and probably four different individuals; two of them are of 

 right valves, and two probably of left valves, all of pretty well grown speci- 

 mens. The specimens being entirely too poor for description or illustration, 

 I have copied both Conrad's description and figure. 



The specimens are the property of the Academy of Natural Sciences 

 at Philadelphia. 



