160 ACT 



A. DANAIDA Dall. PI. 20, fi.-r. 



Shell elongated, moderately pointed, polished, white, and having 

 about six whorls; spiral sculpture of (on the spire) six, or (on the 

 last whorl) over twenty-five punctate grooves, more crowded an- 

 teriorly, but with two or three coarser than the rest, just in advance 

 of the suture; between these original grooves in the latter half of 

 the last whorl intercalary single or double grooves appear, which are 

 seldom quite as deep as the originals, and at first are not punctate, 

 but at last, and especially near the anterior extreme of the shell, be- 

 come nearly as well marked as the original series ; transverse sculpt- 

 ure consisting only of lines of growth, by a peculiar thickening of 

 certain of which when they cross the grooves the punctate appear- 

 ance is produced ; nucleus eroded, minute ; suture appressed, distinct, 

 but the thin appressed anterior margin seems peculiarly liable to 

 erosion, which in some cases takes place, so as to produce the 

 appearance of a channelled suture; whorls slightly rounded ; outer 

 lip thin, simple, somewhat produced in the middle, passing imper- 

 ceptibly into the thin twisted pillar, which is slightly reflected, and 

 bears one inconspicuous, very oblique fold ; body with a thin layer 

 of callus ; aperture rounded in front, rather narrow, pointed behind : 

 no umbilical chink in this or any of the preceding species. Lon. of 

 shell, ll'O; of last whorl, 7'75 ; of aperture, 6'25. Max. lat. of 

 shell, 5-25 ; of aperture, 3'0 mill. (Dall). 



Off Tortugas, 339 fms. (Blake). 



A. danaida DALL, Bull. M. 0. Z. ix, p. 42, 1881; Blake Rep. 

 Gastr., p. 42, pi. 17,f. 12. 



One specimen and a fragment obtained. It is an elegant and 

 excessively punctate species, which looks as if it might have been 

 i by a shower of little coins. 



A i versus Dall. PI. 20, figs. 31 



Shell short, thin, inflated, waxen white, polished, with five or six 

 whorls and a rather acute spire ; nucleus minute, more or less im- 

 mersed, eroded to some extent in every >pe<imen; apical whorls 

 smooth, politbed, rounded; suture very distinct, in the majority of 

 cases not channelled ; the apical whorls with two or three distant 

 narrow grooves across which in some cases, pass elevated lines of 

 growth which appear nowhere rise, or, if at all, only in the .-uture 

 near the apex : la-t whorl forming the largest part of the shell, in- 

 flated, provided with ten or eleven spiral grooves, which are nearer 



