236 NEW YORK STATE MUSEUM 



Sculpture casts show moderately broad vertical sicae. Surface with radial 

 ribs, which are flat, simple, continuous without increase, and are separated 

 by narrow sulci. The number of these plications is from 20 to 28, and a 

 considerable number of the anterior of these do not start from the beak 

 but take origin along the sical margin. Only traces of concentric striae 

 are present. The hight of a typical specimen is 8.5 mm ; length 10 mm. 



To this species are referred a number of specimens of quite small 

 shells, in which there seems to be some variation in the coarseness of 

 surface plication. One of these is specially peculiar in presenting an 

 unusual elongation of the antelateral extremity beyond the normal basal 

 outline of the shell. This is a limestone specimen with natural convexity 

 and full outline. The same example shows very clearly a relatively very 

 large anterocentral distinctly elevated (on the cast) single adductor muscle 

 scar which covers more than one half the diameter of the valve at this 

 place. Traces of a similar scar are to be seen on a specimen from the 

 shale. This species differs from L. clymeniae, L. eriense and L. 

 velatum in its more acuminate outline and coarser plications. 



Habitat. Genesee province; Naples subprovince ; in the Naples 

 shales, Parrish gully, Naples ; and in the Styliola limestone, Genundewa, 

 Canandaigua lake. 



Lunulicardium (Chaenocardiola) furcatum sp. nov. 



Plate 4, fig. 7 



Shell subtriangular in outline, beak slightly posterior, sical margin 

 long and straight, basal margin a low broad curve rounding rather abruptly 

 backward into a relatively narrow posterior curve. Surface quite depressed, 

 flattened over the pallial region, covered by radial plications which show a 

 distinct forward sweep over the surface. The plications are numerous, 

 distinctly flat topped with flat interspaces, are obsolete in the umbonal 

 region and seem to be devoid of concentric lines. They are highly 

 irregular in size specially on the posterior portion of the shells, small ones 

 rapidly intercalating among the larger and on the anterior slope the large 

 ones are distinctly split medially by a groove, multiplication taking place 



