THE MUSSEL FISHERY AND PEARL-BUTTON INDUSTRY. 
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bottom, and are reported to be <]uite active, moving toward the shores in the morning 
and back toward the channe] in the evening, making conspicuous tracks on the 
bottom. These mussels, which are long and narrow, reach a length of (! inches, and 
are highly valued in button-making. 
A smaller species is the “slough sand shell” {Lampsilis fallaciosus), which seems 
to be most common in or near the mouths of narrow arms of the river, especially coves 
that extend into islands. It is less generally distributed in the river than the “yellow 
sand shell,” occurs in much smaller beds, and is now quite scarce in most places where 
extensive fishing has been carried on. It is considered very good for buttons, having 
a beautiful pearly color and uniform thickness. It has been iiractically caught out in 
the vicinity of Muscatine, near which place a bed yielded 10 tons a few years ago and 
ceased to exist. 
Ranking next to the sand shells in abundance is the species known as “rnucket,” 
“mouket,” or “mougat” [Lampsiliti Ikjamentimis). It attains a length of G inches, but 
the average size of those utilized is only about 4 inches. It has a dark-brown exterior 
and a creamy-white nacre. Only second-class buttons are made from it, as the front 
part of the shell is thin and the back part brittle. ISTew factory hands are usually set 
to work on this species. 
One of the best mussels for buttons is known as the “ deerhorn” or “buckhorn” 
[TritUjonia verrucosa). It is not abundant, and the supiily is irregular and uncertain. 
It attains a large size; examples over 9 inches long have been taken from the Iowa 
River, and in the Mississippi it reaches a length of 0 inches or over, the average being 
about 5 inches. 
A rare but very desirable mussel is the species locally known as the “ butterfiy ” 
(rUujiola securis), in allusion to tlie shape of the valves. The flat shell is of small 
size, but thick and of a fine color. The epidermis is reddish-brown, marked by dark 
radiating lines. In 100 tons of miscellaneous shells from the Mississippi River, in the 
Muscatine section, there are likely to be only a few hundred pounds of “butterflies.” 
In the Illinois, Ohio, and some other tributaries of the Mississippi, this mussel is 
abundant. 
A mussel not very highly regarded by the button-maker, but sometimes used, is 
the so-called “ blueqmiut ” ( Quadruhi undulata). It has a large, thick shell, with a wavy 
exterior; the nacre at one end is usually of a bluish or purplish color, in contrast with 
the white surface of the remaining part. The chief objection to its employment in 
button-making is the lack of uniformity in color. 
Another species not highly regarded is the “ hatchet-back,” or “ hackle-back,” 
[Symplipnota complanata). This is a large, black mussel with a projecting wing. The 
valves are thin and of an undesirable color, and only a very small section of each is 
suitable lor buttons. 
Several species of “pocketbook” clams {Tjampsilis cnpax and L. veniricosus) are 
more or less abundant and yield a good button of medium thickness. They are 
characterized by having rounded valves of great depth. 
Nearly all the tributaries of the Mississippi in this section contain mussels in 
some abundance, but no mussel fishing is done in them. The Iowa and Cedar rivers, 
for instance, have a good supply of large “muckets” and large “blue points,” which 
are the principal species; also pink aud white “hatchet-backs,” a few fine “sand 
shells,” a very few “niggerheads” and “pocketbooks,” and some extra large “deer- 
