338 REPORT ON ALBATROSS MOLLUSCA DALL. 



Benthonella gaza Dall. 

 Plate xi, Fig. 5. 

 Benthonella yaza Dall, Bull. Mas. Coaip. Zool., xvni, p. 282, June, 1889. 



Shell elongated, glistening opaque wbite, extremely thin, with two 

 and a half larval and five later whorls. Nucleus trochif'onn, brown, 

 polished, with a single carina above the periphery ; other whorls full, 

 rounded, the earlier ones marked with a few faint flexuous transverse 

 waves, the rest with only lines of growth. The whorls are full and 

 rounded, the suture distinct ; base full, rounded, with a small umbilicus, 

 in front of which is reflected the thin inner lip; aperture rounded, lip 

 slightly reflected, not thickened. Longitude of shell, 8; of last whorl, 

 4; maximum latitude of shell, 4 mm . 



Hab. — Station 2352, west of Cuba, in 4G3 fathoms, coral ; also at Sta- 

 tion 2394, between the delta of the Mississippi and Cedar Keys, Florid;), 

 in 420 fathoms, mud; temperature 4L°.8; Station 2751, south of St, 

 Kitts, West Indies, in 687 fathoms, ooze; temperature 39°.9 F. Station 

 2754, in 880 fathoms, ooze, east from Tobago; temperature 37°. 9; and 

 Station 2760, 90 miles north from Ceara, Brazil, in 1,019 fathoms, broken 

 coral; temperature 39°.4 F. 



This species may be regarded as the type. Its polished white 

 rounded simple whorls and brown tip present an elegant appearance. 



Family ADEOEBID.E ! 



Genua ADEORBIS Wood. 



Adeorbis sincera sp. uov. 



Plate xn, Fig. 2. 



Shell small, depressed, white, with a deep olive epidermis, four- 

 whorled ; nucleus not differentiated, smooth, regular ; surface of shell 

 polished, sculptured only by incremental lines; whorls full and regu- 

 larly descending; after the first whorl nearly all specimens have a flat- 

 tened area in front of the suture, strongest in the apical whorls, where 

 it is usually bounded in front by a sharp cariua or angle. on the whorl; 

 this decreases and is nearly obsolete on the last whorl ; in the same 

 way the umbilicus is generally bounded by a well-marked angle which 

 is visible even on the margin of the aperture, and is less prominent on 

 the adult than in the young; other specimens have the whorls evenly 

 rounded; umbilicus wide; a/perture complete, continuous, nearly cir- 

 cular, except at the upper end of the outer lip where it joins the body, 

 where there is a slight angle; young and strongly cariuate specimens 

 show angles in the margin corresponding to the carina. Maximum 

 diameter, 3.25; minimum diameter, 2.5; altitude, 2.6'"'". 



Hab.— Station 2668, off Fernaudina, Florida, in 294 fathoms,, shelly 

 bottom ; and Station 2756, off the Para River, Brazil, in 391 fathoms, 

 sand; temperature 40°.4 to 46°.3 F. 



