346 REPORT ON ALBATROSS MOLLUSC A— DALL. 



Turcicula Bairdii Dall, 

 Plate vii, Fig. 3. 



Turcicula Bairdii Dall, Ball. Mns. Comp. Zool., xvm.pp. 37G-378, Jane, 1889, 



Shell large, turbinate, elevated, thin, inflated, with four and a half or 

 five whorls, of which the last is much the largest; surface apt to be 

 eroded, but where perfect covered with an extremely thin dense verui- 

 cose pale apple-green epidermis ; whorls inflated ; suture deep, not chan- 

 neled; apex moderately pointed; spiral sculpture of (I) numerous fine 

 faint rather irregular scratches or impressed lines; (2) sparse slightly 

 elevated revolving bauds which are usually more or less nodulous, the 

 nodules when prominent being sharp and laterally flattened as if pinched 

 up ; of these there are. on the upper whorls usually three series between 

 the sutures, of which one at the periphery is the most prominent and 

 persistent, the next one behind it, half way between the periphery and 

 the suture, being the least marked; on the base the cinguli are six or 

 seven in number, becoming narrower toward the axis, smaller than 

 those behind the suture, with smaller, less prominent, rounder and more 

 numerous nodules ; there is some variation in number and strength of 

 all the cinguli, but that on the periphery is the most prominent and 

 constant; the whorls are particularly round and inflated above and be- 

 low, so that the outline of the aperture is often nearly circular ; interior 

 of the aperture brilliantly pearly, a thin wash of callus on the body ; 

 the outer lip very slightly thickened and distinctly reflected in the 

 adult; pillar thin, simple, arching roundly into the curve of the base 

 without any interruption, angle, or tooth; axis imperforate;- the exter- 

 nal sculpture showing through the thin shell. Altitude 50 ; maximum 

 diameter 42 mm . Maximum diameter of operculum IS" 1 " 1 , "with about 

 twelve whorls. The operculum is externally polished, smooth and 

 deeply concave ; the iUuer side presents a minute central rounded ele- 

 vated point; the margin is very thin but entire. 



Hab. — Station 2839, off San Clemente Island, California, in 414 fath- 

 oms, sand; bottom temperature not registered. 



Soft parts. — The sides of the foot below the epipodial line are gratui- 

 tous; above the line the surface is rather smooth. Much of the surface 

 is apt to be covered with a layer of blackish or olivaceous substance, 

 like solidified mucus or paint, which seems to belong to the animal, yet 

 is wholly external to the cuticle. The foot is broad, not very long, 

 bluntly pointed behind, the front edge straight, double, the lateral an- 

 gles pointed; the upper layer of the edge is smooth and turgid in most 

 of the specimens ; it is not indented in the median line. 



The muzzle is stout, circularly wrinkled, a little expanded at the 

 disk; the oral disk is not marginated; its surface is finely granulose; 

 it is angulated at its lower outer corners and medially iudented be- 

 low. There are no oral palps or tactile appendages. 



