INTRODUCTION. 



It is proposed to give, in the following pages, a brief account of the 

 economic moUusca of the United States, together with a description of 

 the manner of conducting the various fisheries and their dependent 

 industries. Minute detail of matter, whether of biological or ecouoniic 

 interest, is not attempted; the design is to supplement the molluscau 

 exhibit by an explanatory pamphlet, which will be illustrated by the ob- 

 jects exhibited. The information given is obtained chiefly from Profes- 

 sor Yerrill's pa])ers on the Invertebrates of Vineyard Sound, i)ublished 

 in the Eeport of the United States Commissioner of Fish and Fisheries, 

 and from the advance sheets of the Reports of Mr. Ernest Ingersoll on 

 the Shell-Fish Industries of the United States, published by the Census 

 Bureau. Many other authorities, too numerous to mention, have also 

 been consulted. 



The total annual product of the shell-fish industries of the United 

 States amounts to 24,859,04-4 bushels, valued at $14,020,187. This total 

 is divided among the various fisheries according to the followiijg- table : 



Name. 



Nnmber 

 bushels. 



Value. 



Oyster fishery . . . 



Clam fishery 



Mussel fishery .. 

 Scallop fishery. . 

 Abaloue fishery 



22, 195, 370 



1, 955, 580 



600, 000 



108, 094 



$13, 438, 852 

 996, Hii5 

 37, .500 

 28, K2.-. 

 127, 705 



While the oyster industry, on account of its importance, deserves the 

 most and first attention, yet, as the collection on exhibition is part of 

 that of the ISTational Museum, it is deemed best to maintain the original 

 systematic arrangement, and therefore the most highly organized of the 

 the mollusca, the Cephalopods are first considered. 



MOLLUSCA CEPHALOPODA. 



The most recent authorities assign thirty species of cephalopods to 

 the fauna of the eastern coast of North America. While so numerously 

 represented, however, only a few of the species are found in sufficient 

 abundance to make them of commercial value. These comprise Omma^- 

 trcphes iUecebrosa, LoUgo pealii, LoJigo brevis, and the gigantic squids 

 {Archltcuthis) of Newfoundland and adjacent coasts; of these, the most 

 abundant and widely distributed is 

 [3] 



