Mollusks 5 A 



The portions of the Arctic region which may be reached with relative ease 

 have been so thoroughly explored for mollusks that little hope is justified for 

 the discovery of undescribed species. It is therefore gratifying that the work 

 of the members of the expedition has been what is really unexpectedly successful 

 in this line. 



I have to thank the authorities in Canada, for the care they have taken 

 to do everything that might lighten my labour in preparing this report, and 

 the Direction of the United States National Museum for the free use of all 

 their facilities during its preparation. For the accuracy of the station numbers 

 Mr. Johansen is solely responsible. 



LIST OF SPECIES COLLECTED WEST OF THE DELTA OF THE MACKENZIE 



RIVER. 



Nucula tennis Montagu, 23 1 . 



Leda (Portlandia) arctica Gray, 23, 27s. 



Leda minuta Fabricius, 23. 



Leda pernula, 23. 



Leda radiata, Krause, 23. 



Leda intermedia Sars, 206-c, 2Qd. 



Leda collinsoni Dall, 27s. 



Yoldia my alis Couthouy, 23. 



Yoldia limatula Say, 23 ( + hyperborea Loven.) 



Mytilus edulis Linne, 206-c; 20d, 24, 60a, 200. 



Musculus Icevigatus Gray, 27s, 281, 24, 23. 



Musculus niger Gray, 24. 



Crenella aff. rotundata Dall, 27s. 



Pandora sp., 27s. 



Lyonsia arenosa Moller, 27s, 24. 



Astarte borealis Schumacher, 23, 24, 26, 27s, 281, 28t, 54e. 



Astarte polaris Dall, 54e. 



Astarte alaskensis Dall, 54e. 



Cardium calif orniense Deshayes, 206-c; 20d, 200. 



Cardium corbis Martyn, 60a. 



Cardium ciliatum Fabricius, 23. 



Serripes gronlandicus Gmelin, 2Qd, 23, 24. 



Serripes laperousei Deshayes, 22. 



Saxidomus giganteus Deshayes, 60a. 



Protothaca staminea Conrad, 60a. 



Liocyma beckii Dall, 23, 24, 27s. 



Tellina (Peronidia) lutea Gray, 20d, 200. 



Macoma calcarea Gmelin, 23, 24. 



Macoma incongrua Martens, 20d, 60a. 



Macoma inquinata Deshayes, 60a. 



Macoma moesta Deshayes, 24. 



Macoma balthica Linne, 54e, 20d. 



Macoma inconspicua Broderip & Sowerby, 206-c, 20d, 200, 24, 



Spisula polynyma Stm. var. alaskana Dall, 200, 20m. 



My a truncata Linne, 23, 24. 



Mya intermedia Dal], 20d, 24. 



Saxicava arctica Linne*, 20d, 23, 24, 60a. 



Cyrtodaria kurriana Dunker, 20d, 26, 27s, 54e. 



Zirfcea gabbi Try on, 24. 



Coryphella cf. salmonacea Couthouy, 200. 



^he numbers refer to the number of the Collecting Station. See page ?A, et sen. 



