308 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



pervious ; canal short, wide, shallow, with a strong, conspicuously wrinkled 

 siphonal faseiole. Lon. of shell, 20.0; of last whorl, 13.5 ; of aperture, 9.0; 

 max. diam. 11.5 mm, 



U. S. S. "Albatross," station 3355, Gulf of Panama, in 182 fathoms, mud, 

 bottom temperature 54°. 1 F. U. S. N. Mus. 123,014. Also at stations 3354, 

 3387, 3389, 3391, 3396, and 3422, in 141 to 322 fathoms, mud or sand, bottom 

 temperatures from 46° to 56°. 2 F., the range extending from the Gulf of Panama 

 to the vicinity of Acapulco, Mexico. 



Alectrion (Tritia) exsarcus Dall, n. ep. 



Plate 11, figure 12. 



Shell small and rather slender, with three and a half nuclear and the same num- 

 ber (or more) of subsequent whorls ; color pale yellowish with two pale, reddish 

 brown, narrow bands, so applied that when the suture is formed there is a brown 

 band near and on each side of it ; nucleus large, the visible portion having a tur- 

 binate aspect, smooth and polished ; subsequent whorls reticulated, with a distinct 

 but not channelled suture ; axial sculpture of (on the last whorl sixteen) strong, 

 vertical, rounded ribs, which entirely cross the whorls and have a particular promi- 

 nence (ill-defined) just in front of the suture ; lines of growth feeble, surface pol- 

 islied, periostracum thin, yellowish ; these ribs are crossed by (on the penultimate 

 whorl five or six, on the last whorl fourteen) strong, rounded, somewhat flattened 

 spiral threads, of which the second in front of the suture is a trifle larger than the 

 otliers and may be articulated with brown and white ; these threads are not nodu- 

 lous, but become a little turgid when they cross the ribs, and are separated by sub- 

 equal, or, on the base, slightly wider flattisb interspaces ; aperture ovate, the outer 

 lip thin (possibly when older varicose ?), with eight or nine lirae internally; inner 

 lip with a thin, smooth coat of callus ; pillar short, its anterior margin keeled and 

 twisted ; canal sliort, recurved, proximally constricted ; siphonal faseiole distinct, 

 with a strong keel behind. Length of shell, 9.0 ; of last whorl 5.5 ; of aperture, 

 3.25 ; max. diam. 4.5 mm. 



U. S. S. " Albatross," station 4642, near the Galapagos Islands, in 200 fathoms, 

 ooze, bottom temperature 48°. 6 F. U. S. N. Mus. 110,565. 



The operculum is normally uassoid. Witli this specimen were dredged some 

 gorgonian cores supporting rows of nassoid ovicapsules probably belonging to 

 this species. They are spatuliform, flat, with a small peduncle, the sides chan- 

 nelled, the lateral and up|)er edges projecting and, above, somewhat wavy or 

 denticulate. They were about a millimeter and a half in height and somewhat 

 less in width. 



Alectrion (Tritia?) goniopleura Dall, n. ep. 



Shell small, decollate, immature, comprising three whorls, rather rapidly en- 

 larging, straw-color, with a slight brown band at the shoulder ; suture deep, not 



