46 BUIvLETiN OF THE BUREAU OF FISHERIES. 



through which he worked with a rake.** Such photographs could not be duplicated 

 now, for each sheller would have to work a large area, and probably no considerable 

 quantity of shells could be taken without more ice cutting than the value of the product 

 would justify, even at the higher unit prices prevailing. The practice of winter shelling 

 has, therefore, been discontinued. 



APPARATUS AND METHODS OF FISHERY. 



BAR AND CROWFOOT HOOKS. 



Principle of Capture. — This method of mussel fishery is the one in most general 

 use to-day, since it is adapted for the greatest variety of conditions, is easily operated 

 even by the inexperienced, and the construction and maintenance involve slight 

 expense. The method is based on the characteristic habits of fresh-water mussels, 

 which lie habitually half embedded in the bottom, with the hinder end of the shell 



Fig. I. — Various types of crowfoot hooks. 



directed against the current and slightly gaping. If a stick or hook be inserted into 

 the opening of the shell, the mussel at once closes tightly and will hold for a long time, 

 even while being dragged over the bottom and hauled up to the boat. Mussels are thus 

 sometimes accidentally taken on ordinary fishhooks, while pearl fishermen working in 

 shallow water have long employed a sharpened stick that could be inserted into the 

 opening of the individual mussel. The more elaborate apparatus now used was first 

 brought to the notice of the rivermen of the upper Mississippi early in the spring of 

 1897, 9.nd its use soon spread throughout all of the commercial shell districts. 



Description of Apparatus. — The crowfoot apparatus consists essentially of a 

 bar or brail to which many short lines are attached bearing four-pronged wire hooks 

 arranged at intervals (PI. XXVII, fig. i). By means of a towing line the bar is dragged 

 above the bottom, while the hooks trail on the mussel bed in a direction parallel to the 

 current. When a hook enters a shell opening, the mussel closes firmly upon the hook, 



a Smith, Hugh M.: The mussel fishery and pearl-button industry of the Mississippi River. Bulletin, U. S. Fish Commis- 

 sion for 1898, Vol. XVIII, p. 289-314. Washington, 1899. (See plates 67 and 68.) 



