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THE SHELL-BEARING MOLLUSCA OF 
RHODE !SLAND. 
BY HORACE F. CARPENTER. 
Chapter X LI1—Continued. 
FAMILY PAPHIID. 
This family, according to Tryon’s “S & S. 
Conck., Vol. iii, 161, 1884,” contains two 
genera, Paphia and Ervillia; Paphia being di- 
vided into six sub-genera. In his “ Catalogue 
of the Family Tellinidz,’ he makes a sub- 
family Paphiidz and treats these sub-genera as 
genera. The family contains thirty-three spe- 
cies, only one of which inhabits New England ; 
this is the 
Genus Ceronia, Gray, 1849. 
This genus contains four species, one inhab- 
iting Australia, another Peru, a third ranging 
from England through the polar regions to 
Nova Scotia, and the fourth is 
L60—Ceronia arctata, Conrad. 
Syns: 
Mactra arctata,Con. Mactra deaurata, Con. 
Mactra sub-triangulata, Wood., Griffith. Meso- 
desma arctata, Gould, De Kay, Stimp. Cero- 
nia arctata, Chenu, Binney, Dall, Tryon, &c. 
Shell sub-triangular, wedge shaped, solid, 
very inequipartite, the posterior end very short, 
its lower part truncated; anterior narrowed, 
rounded; surface covered with a shining yel- 
low epidermis; beaks erect; hinge a deep 
spoon-shaped cavity for the cartilage; a long V 
tooth, opening at an acute angle and a straight, 
/ Striated lateral tooth on each side of it. Length, 
1% inches, height, one inch, breadth, 33 
This species was described by T. A. Conrad 
in Journ. Acad. Nat. Sci , Phila., vi, 257, 1830. 
It is found abundantly in Mass. Bay, and at all 
points north of Cape Cod to the St. Lawrence 
River. Perkins does not mention it in his 
“Molluscan Fauna of New Haven,” but S. 
CHESTNUT HILL, PHILADELPHIA, PA., JANUARY, 1888. 
No. 7. 
Smith has found it at Montauk, Long Island ; 
a few specimens have been found at Nantucket, 
and Tryon quotes it from Massachusetts and 
Rhode Island, but I have never found it in our 
waters. 
FAMILY SEMELIDA. 
This family contains nine genera and about 
one hundred and ten species, of which only 
one inhabits New England. 
161.—Cumingta tellinotdes, Conrad. 
Syns : 
Mactra tellinoides, Con., Russel, De Kay. 
Cumingia tellinoides, Con., Gould, Stimp., 
Dall, &c. 
Shell elongated, triangular-ovate, thin and 
fragile, white, nearly equipartite, anterior -tu- 
mid, broad and rounded, posterior compressed, 
pointed and warped like a Tellina; beaks cen- 
tral, not inclining to either side; surface with 
sharp, elevated lines of growth crossed by mi- 
croscopic radiating lines; interior glossy white; 
lateral teeth distinct in the right valve, but not 
in the left. Length, 2; height, 2; breadth, 
4. Described by T. A. Conrad in Journ, Acad. 
Nat. Sci., Phila., vi, 258, 1830. Habitat from 
Cape Cod to Florida, (Verrill). Very rare at 
New Haven, (Perkins), Florida, (Conrad,) 
North Carolina, (Coues). Gould says: ‘It 
is found abundanily in the region of New Bed- 
ford, Martha’s Vineyard, and probably may be 
found everywhere south of Cape Cod.”’ It has 
not yet been found in R. IJ. to my knowledge. 
The genus Cumingia was named in 1833 by 
Sowerby, and dedicated to the late Hugh Cum- 
ing, a distinguished collector of shells, the spe- 
cies of which, ten in number, inhabit sponges, 
sand and the fissures of rocks, in consequence 
of which, the valves often assume an irregular 
appearance. | 
PAMILY TELIERNTD AR, 
This family contains sixteen genera, and in- 
cludes many of the most beautiful shells of the 
tropics, with highly polished surfaces, and 
