REPORT ON THE GASTEROPODA. 107 



pendicular. Outer lip thin and sharp, not patulous, not descending, with an open not deep 

 angular sinus near the suture, from which the line of the edge runs outwards uninter- 

 rupted across the second spiral, and forms a round projecting point, retreating again so as 

 to form a second sinus, smaller and sharper, in the line of the basal carina, from which it 

 again runs outwards into a rounded point in the exterior basal furrow, and from this again 

 retreats, sharply changing its direction on the fifth spiral, and then again retreating, as 

 before, to the sixth spiral, where it forms a third, open, obtuse-angled sinus, and then 

 passes in regularly to the centre. Pillar-lip twisted, with a deep rounded sinus above, a 

 strong twisted tooth at about two-thirds of its length, another narrower rounded sinus 

 below, and a sharp tooth at the point. The pillar is strengthened by a pad, which is spread 

 out on the base so as to cover the seventh (counting from the suture) spiral, and envelops 

 the pillar so as to leave a minute furrow behind it, but ceases at the pillar-tooth. Umbilicus 

 ' completely closed (but in some young specimens presenting a minute hole, see var. lineata, 

 Wats.) H. 0-2 in. B. 0-14, least 0-12. Penultimate whorl, -04. Mouth, height '07, 

 breadth 0-06. 



Dr Gwyn Jeffreys says that the operculum of this species " is ear-shaped, very thin, paucispiral 

 (having only two whorls); the spire very small, excentric, and placed on the columellar side, thus 

 resembling somewhat that of Solarium and Adeorbis" This form, according to Quoy and Gaimard, 

 is shared by Euchelus, Philippi's subgenus of Trochus. In one rather young specimen of the species 

 from Station 24, the dried-up remains of the animal are preserved, but I could not persuade myself 

 to break the shell so as to secure the operculum. 



To the young specimens from Pernambuco, var. lineata, Wats., I have put a query ; for though 

 I cannot separate them, still the longitudinal sculpture is stronger, and there is an umbilicus. 



Some further and very recent observations on this species are given by Professor Verrill in his 

 Mollusca of the New England Coast, p. 187, where he says, "Jaws thin, brown, irregularly ovate, 

 the outer half covered with small tesselated elevations, becoming more prominent, blunt, or spatulate 

 at the margin. Odontophore very small and slender; median tooth minute, thin, with the tip bent 

 forward and ending in a minute central denticle ; inner laterals with the tip small, curved forward, 

 flat, unarmed, almost half as wide as the median ; outer laterals long, slender, very acute, strongly 

 curved." 



2. Seguenzia ionica, Watson 1 (PI. VII. fig. 3). 



Seguenzia ionica, Watson, Prelim. Report, pt. 3, Journ. Linn. Soc. Lond., 1878, voL xiv. p. 589. 



„ Dall, "Blake" Moll, Bull Mus. Comp. ZooL Camb., U.S.A., 1881, vol. ix p. 48. 



Station 24. March 25, 1873. Lat. 18° 38' 30" N., long. 65° 5' 30" W. Off Culebra 

 Island, West Indies. 390 fathoms. Pteropod ooze. 



Station 73. June 30, 1873. Lat. 38° 30' N., long. 31° 14' W. West of Azores. 

 1000 fathoms. Pteropod ooze. 



Habitat. — Gulf of Mexico. 



1 So called from its resemblance to the volute of the Ionic capital. 



