DALL: MOLLUSCA AND BRACHIOPODA. Die 
whorl just behind the periphery; on the fasciole are six or seven smooth rounded 
subequal spiral threads with equal or wider interspaces, more crowded anteriorly ; 
beyond the shoulder are nine similar but coarser threads, sometimes entire, some- 
times flattened or even medially suleate on top, extending over the base, and on 
the region of the canal as many more, smaller and more distant, crossed by obvious 
incremental lines; aperture elongate, rather narrow, anal sulcus very wide but 
shallow; outer lip produced, evenly arcuate to the end of the canal, not constricted 
at the base of the whorl; pillar lip smooth, pillar short, obliquely truncate, gyrate, 
the axis pervious; canal wide, hardly differentiated. Lon. of shell, 48; of last 
whorl, 35; of aperture, 26; max. diam. 16.5 mm. 
U.S8.5. “ Albatross,” station 2859, Pacific Ocean, in 1569 fathoms, ooze, bottom 
temperature 34°.9 F. U.S. N. Mus. 122,563. 
The soft parts and operculum were not obtained, so the shell is only provision- 
ally placed in this group. It recalls the shell described by me in the Blake Report 
from Cuba under the name of Aforia hypomela, but which is perhaps an Ireno- 
syrinx. The latter has the spiral sculpture more delicate, the posterior slope of 
the whorls flattened, and the whorls more numerous. 
Ancistrosyrinx cedonulli Reeve. 
Pleurotoma cedonulli Reeve, Proc. Zool. Soc., London, 1848, p. 185; Conch. Icon., 
Pleurotoma, fig. 117 a. 
U.S. 8. ‘ Albatross,” station 2799, in Panama Bay, in 30 fathoms, mud; and 
station 3391, Gulf of Panama, in 153 fathoms, mud, bottom temperature 55°.8 F. 
U.S. N. Mus. 123,102. 
Several fairly well preserved specimens were obtained, as above, but without 
the animal. There is no doubt that the species belongs to the same group of 
Turritidae that includes the Atlantic coast 4. elegans and A. radiata Dall, which 
have granular sculpture and an operculum like Drillia. That Tryon, who knew 
the Panama species only from an inadequate figure, should have regarded it as the 
young of the Japanese Columbarium (with a wrong locality) was under the cir- 
cumstances not extraordinary, though erroneous. The relations of this group to 
Cochlespira Conrad, its Eocene precursor, have already been alluded to (see page 
257). In view of the ambiguity of Reeve’s figure it might be well to say that this 
species has no axial sculpture on the whorls between the carina and the base ex- 
cept what may be due to accidents during growth. The surface is normally smooth 
and polished, above and helow the carina, and of a delicate pale brown color. 
Steiraxis aulaca Datu. 
Plate 2, figure 5. 
Pleurotoma (Steiraxis) aulaca Dall, Proc. U.S. Nat. Mus., 1896, 18, p. 14. 
Shell large, solid, white, fusiform, with about five whorls (nucleus eroded) 
covered with a pale straw-colored epidermis; whorls rounded, with rather distinct 
VOL. XLIII. — No. 6 18 
