VI. REPORT ON THE MOLLUSKS. 



BY W. H. DALL. 



Opportunities for collecting inolliisks are not very good at this northernmost point of the 

 United States. The shores are covered with snow during a large part of the year, and the w;u 

 with ice. The latter is frequently grounded and driven npoii the beach or over the shoal water 

 adjacent to the beach, so that mollusks must find it a rather disagreeable station to inhabit, pro- 

 vided they can secure themselves against free/ing or crushing. There are no fresh-water .shells, 

 though it is probable that a few species occur at a not very great distance inland. The shore is 

 composed of sand and gravel, which is constantly undergoing minor changes. There are few sea- 

 weeds, and the phytophagous littoral mollusks, so abundant at most stations more favorably situ- 

 ated, are altogether absent. There arc some places along this stretch of coast where strong currents 

 meet and ice seldom grounds; where eddies permit the deposition of a moderate amount of mud 

 and occasional small seaweeds manage to exist, anchored on little pebbles or riding ou the backs 

 of crabs. In such places mollusks abound, individuals, if not species, being numerous. One such 

 locality is well known as a good dredging ground, namely the vicinity of the Seahorse Islands or 

 < 'ape Franklin, from a couple of hauls near which the best part of the present collection was obtained. 

 A few additions were made to the list in Norton Sound, Unalashka Harbor, &c., but the opportuni- 

 ties for dredging or surface-collecting were not abundant. Considering the disadvantageous cir- 

 cumstances, the naturalists of the party must be commended for their energy and success. 



SPECIES COLLECTED. 

 CEPHALOPODA. 



Octopus grcenlandicus (Dew.) Minx-h. 



, A tine specimen on the beach near the station. This has been examined by Professor Verrill, 

 who agrees with the writer as to its distinctness from the 0, ptinctatus Gabb, so common further 

 south. Museum number, 40953. 



PTBBOPODA. 



Itimaciiia Pacifica Dal I. 



On the surface of the water off the station in -Inly, 1882. Collectors' number, 650; museum 

 number, 40954. This pretty species, which is very much larger than the Atlantic form, was origi- 

 nally described from the North Pacific. 



GASTROPODA. 



IVI.MONATA. 

 Cochlicopa lubrica Miillrr. 



CiomUit su>M-yHii<li-ii-ti I. dim rt, Si-imcr Hri-nrd, vol. ii, No. *. ]>. 17,', Hovfon, Jinn- It!, I*-* I. 



Two specimens in moss from the tundra near Uglaiimi. 



Zonitea (Conulus) Steamsii Bluiul. 



JTyalina nntirn Li-lniri-t, l.r..|>. 17'J. 



Ten or twelve specimens from the tundra moss. This has been erroneously referred to Iho 

 genus or section Mirroplii/xit. 



If. Ex. 44 23 



