646 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [6] 



found in southern waters, are curiously associated, in this region, with 

 genera and species which have hitherto been regarded as exclusively 

 northern or even Arctic, manj' of them having been first discovered in 

 the waters of Greenland, Spitzbergen, Northern Norway, Jan Mayen 

 Land, etc. 



Among the northern species which had not been found previously 

 south of Cape Cod, the following were dredged : Troplwn clathratus, 

 972,976; Acirsa costulata { = borealis),965 -, Amauropsis Islandica {=heli- 

 coides) ; Margarita cincrea, 981 ; Cylichna Gouldii, 973 : Odostomia {Me- 

 nestlio) striatula, 980. 



Dolium Bairdii Verrill and Smith. 



A moderately large species, having nearly the form of D. perdix and 

 D. zoriatum. Male. Shell broad ovate, with seven broadly rounded 

 whorls ; spire elevated, apex acute ; nuclear whorls about three, smooth ; 

 suture impressed, but not deep, nor channeled ; the last whorl is some- 

 what flattened (perhaps abnormally) below the suture, for some dis- 

 tance, corresponding to an inward flexure of the outer lip. Aperture 

 elongated, irregularly ovate ; outer lip regularly rounded, except for a 

 short distance posteriorly, where it is slightly incurved, its edge is ex- 

 curved, acute externally, distinctly but not prominently creuulated 

 within, except posteriorly, where a posterior canal is slightly indicated; 

 columella straight ; canal short and broad. The sculpture is peculiar: 

 it consists of numerous (about 40 on the last whorl) rather prominent, 

 squarish, clearly defined revolving ribs, less than 1°"" broad, separated 

 by interspaces of about the same breadth, in which there is usually one 

 small narrow rib, alternating with the larger ones ; sometimes there are 

 two or more small ones. The whole surface, both of ribs and inter- 

 spaces, is covered with fine and regular transverse, raised lines. The 

 surface is covered with a very thin pale olive-yellow epidermis, easily 

 deciduous when dry. Color white, except that the larger ribs are alter- 

 nately light brown and white, and the apex, consisting of about three 

 smooth nuclear whorls, is dark brown. Length, 68™™ ; breadth, 56™™ ; 

 length of aperture, 53™™. 



The animal is well preserved. Proboscis blackish, exserted about 

 20™™, thick (8™™) and clavate at the end, which is surrounded by a 

 sort of collar, with a finely wrinkled or creuulated, white edge. Head 

 large, with a prominent rounded lobe in front. Tentacles large, 

 elongated (10™™), stout, tapering, obtuse. Eyes small, black, on dis- 

 tinct but slightly raised tubercles at the outer base of the tentacles. 

 Head, tentacles, and siphon-tube dull brown. Penis very large (50™"» 

 long, 12™™ broad), twisted and thickened at base, flattened distally, 

 terminating in a slightly prominent obtuse lobe at the tip ; a well-marked 

 groove runs along the posterior edge to the tip. 



Oif Martha's Vineyard, station 945, 202 fathoms. Station 1036, 94 

 fathoms; one young specimen and large fragments 



