58 BULLETIN OF THE BUREAU OF FISHERIES. 
by hand to a fore-and-aft position (Pl. XXX, upper figure); it is then lowered into 
the water by unwinding the windlass. The line from the windlass passes through a 
block overhead (not shown in the picture) and down to the bridle of the dredge. The 
two pulleys through which the bridle passes should be noted on the ends of the dredge 
handles. When the brake on the windlass is thrown off, the dredge falls to the 
bottom, and the dog releases automatically. The dredge now rests on the bottom, 
covering a space 3 by 6 feet, with the tines of the two ends sticking into the substratum. 
The first effect of turning the windlass, after taking up the slack, is to lift the ends of 
the handles and bring them together, thus causing the dredge to close. As the dredge 
closes, the tines thoroughly rake the bottom, and when completely closed every mussel 
and rock in the space covered, except those so small as to pass through the openings, are 
taken in the basket. Continued winding of the windlass brings the dredge out of the 
water, when it can be lowered into one of the boats and opened. All débris must be 
sorted out and thrown away. A small hand rake, like a flower rake, is used to clear the 
small stones which may have been wedged between the tines. In view of the contin- 
gency that the dredge may be fouled by a log or heavy stone, it is necessary to have a 
clearing line attached to one end of the dredge. A small windlass must be used to operate 
this line if the dredge is very heavy. ‘The effect of hauling on this line is to open the 
dredge, which may have been partly closed, and bring it up to the surface; the haul is of 
course lost in such a case. Heavy dredges are more effective than the light ones. 
The cost of the larger dredge was $65 complete, with boats and all; but there was 
very small expense for labor, as the work was done during the slack season and largely 
by the owner. The ordinary complete cost of such an outfit would be $100 or more. 
If the openings between the tines are wide enough, the small shells will not be re- 
moved from the bottom. Comparing the dredge with the crowfoot drag, it may be 
noted that the latter takes mussels by chance and that repeated dragging over the same 
bottom is necessary to make an approximately clean catch, while the former makes a 
clean haul of only the mussels large enough to be taken. It will be seen, therefore, that 
the crowfoot apparatus, although less effective over a given small portion of bottom, is 
actually more destructive to the young mussels. 
An entirely new form of dredge has recently been invented, which is operated by 
power and brings the mussels continuously from the bottom by means of an endless 
chain and buckets. No detailed description can be given at this time. 
LOCAL MODIFICATIONS OF METHODS. 
Various other forms of apparatus have been devised at different times and put into 
temporary use, but none of them seems to have won a place in the established methods of 
fishery. There are many local variations of the typical methods described, but it is 
not practicable to describe them all. Two special modifications of the use of the coke 
fork and of the basket rake were thus described as used in the James River in 191374 
The mussels [at Riverside, S. Dak.] were gathered with a coke or coal fork, having a piece of 2 by 4 
lumber fastened to the handle, the length of this piece being according to the depth of the river. This 
fisherman had a novel way of anchoring his boat. At each end of the boat a hole was bored through the 
bottom large enough to insert a piece of 1.5-inch pipe, makinga water-tight joint. These perpendicular 
a Coker, R. E., and Southall, J. B.: Mussel resources in tributaries of the upper Missouri River. Appendix IV, Report, 
U.S. Commissioner of Fisheries for 1914, 17 p., t pl., map. Washington, rors. 
