FRESH-WATER MUSSELS AND MUSSEL INDUSTRIES. 31 
Often the forward or butt part of the shell is somewhat chalky and comprises 
scarcely more than one-fourth of the shell surface, while the remaining three-fourths 
is too thin and brittle. A noteworthy feature of the shell is the lateral hinge, which 
has a beautiful pearly luster. The cardinal teeth, too, have an attractive form and 
are used in the manufacture of cheap jewelry. 
Lampsilis ovata (Say) (Pl. XVII), the southern pocketbook or grandma, is not 
ordinarily distinguished from ventricosa. It is found in the Ohio River and tributaries, 
as in the Clinch, Holston, and Cumberland Rivers. It is rather thinner and inferior to 
the common northern pocketbook. 
Lampstlis (Proptera) capax (Green) (Pl. XVII), also called pocketbook and confused 
with the others, is not closely related to them in spite of its superficial resemblance. 
It is quite too thin for value in button manufacture. The purply Lampsilis (Proptera) 
purpurata (Lamarck) (Pl. XVIII) is probably related to capax. It is very familiar to 
shellers in Texas, Louisiana and Arkansas, but the thinness of the shell, as well as the 
deep purple nacre, makes it unfit for the trade. It is one of the most beautiful shells. 
Another species which looks something like a young pocketbook, but which never 
attains so large a size, is Lampsilis multiradiata (Lea) (Pl. XVIII) of the Ohio drainage 
and southern Michigan. Its shining greenish-yellow, bright-rayed shell is very attrac- 
tive to the eye. 
SAND-SHELL GROUP. 
There are three sand-shells, the yellow, the slough, and the black. 
The yellow sand-shell, Lampsilis anodontoides (Lea) (Pls. I, XVI and XIX), is the 
most highly prized of all commercial shells. It is never very abundant, but it is probably 
the most widely distributed of all the species discussed. Its distribution as given by 
Simpson is; “‘ Entire Mississippi drainage, except, probably, the upper Missouri. All the 
Gulf drainage from the Withlacoochee River, Fla., to the Rio Grande, and into Mexico.” 
The common name is derived from the clear yellow or brownish-yellow exterior color. 
These shells are too valuable for use in button manufacture; consequently they are 
always sorted out. Many tons of them are bought from the fishermen on the rivers to 
be used for export. Even those that reach the factories in mixed cars are sorted out in 
the yard to be sold again to shell jobbers. In very recent years, however, due to war 
conditions, many sand-shells have been cut into buttons in domestic manufacture. 
Some years ago it was said that the sand-shells were shipped chiefly to France; in the 
few years preceding 1914 the greater part seemed to have been destined for the German 
market, and the price on the rivers in 1913 was $60 per ton. The export was neces- 
sarily interrupted in 1914, but in the early part of 1911 the writer was informed of an 
offer of $92.50 per ton f. o. b. New York, and a consular report from Hamburg quoted 
these shells at prices equivalent to from $108 to $151 per long ton, when niggerheads 
were quoted in the same market at $54, and muckets at from $47 to $119. About 
three pairs of sand-shells (the shells from three mussels) usually make a pound, so 
that the mussels were worth at least 1 cent apiece on the river and, at the date of the 
consular report, 2 cents apiece or more in Hamburg. In 1919, with some export 
demand, yellow sand-shells bring about $90 per ton. : 
The shell owes its value to the following characteristics: (1) Its luster and pearly 
qualities are almost if not quite equal to the marine shells; (2) its texture is smooth and 
