ACTION. 161 



together anteriorly ; these grooves are somewhat zigzag by exigencies 

 of growth, but are not punctate, as in so many species ; other spiral 

 sculpture consisting of microscopically fine slightly zigzag striae, 

 about seventy in the width of a millimeter; transverse sculpture 

 only of most delicate flexuous lines of growth most evident near the 

 sutures; aperture rounded in front, pointed behind; outer lip thin, 

 simple, arcuated toward the periphery, passing imperceptibly into 

 the pillar ; body with a slight callus joining the rather slender 

 pillar which carries one inconspicuous fold. Lon. of shell, 9'0; of 

 last whorl, 7'0 ; of aperture, 5*75. Max. lat. of shell, 5'75 ; of 

 aperture, 3'0 mill. (Dull). 



Yucatan St., off Cape San Antonio, 640 fms. 



A. incisus DALL, Bull. M. C. Z. ix, p. 95 ; Blake Rep. Gastr., p. 

 42, pi. 17, f. 1,16. 



In this, as in the preceding deep-water species, the fold or ridge 

 on the columella is faint, though not entirely absent, and is best 

 seen from the side; in fact, it is almost invisible in all, except A. 

 melampoides, from in front as the figures are viewed. The columella 

 in these figures, however, is drawn as straighter and broader than it 

 really appears; but in these particulars it is very difficult to get a 

 draughtsman who knows nothing of shells to catch the characteristic 

 curves in every instance. (Dull). 



A. EXIGUUS (Bunker) Morch. Unfigured. 



Shell covered-perforate, flesh colored, ovate ; spire elevated, nearly 

 half the length of the shell; last whorl with its lower half sulcate, 

 the bottoms of the grooves punctate ; spire and upper half of the 

 body-whorl smooth; suture subcontabulate, margined by an im- 

 pressed line; columellar fold strong. 



Length 6, diam. 3 mill. (Morch). 



Antilles (Riise). 



Actceon exiguus DKR. mss. MORCH, Malak. Blatter, xxii, p. 169, 

 1875. 



Var. ovalis Morch. Spire shorter, suture margined with two deep 

 grooves. Alt. 6, diam. 3'1 mill. 



A. SPLENDIDULUS Morch. Unfigured. 



Shell elongate-ovate, very solid, whitish, bright and shining. 

 Whorls about 5, the last with impressed spiral lines, punctate along 

 their bottoms, very distant in the middle of the last whorl, but to- 

 ward the base becoming closer and in pairs. Sutural region smooth. 



