66 THE NAUTILUS. 



interesting South Sea shells from places visited by the well-known 

 " Morning Star," and from other sources. 



Unfortunately the limitation of my time allowed only brief glances 

 at a few drawers of this rich material. The following species were 

 among a few shells which Mr. Emerson put aside for me to take 

 home for determination. 



CLAUSILIA EMERSONIANA n. sp. PI. IV, figs. 1 to 5. 



The shell is slenderly fusiform, opaque, vinaceous buff with paler 

 ribs, upper half tapering slowly to an obtuse apex. Whorls about 

 10, the first 2 corneous, very convex, delicately striate, the tip 

 glossy ; riblets then begin, at first rather well spaced on the convex 

 whorls. In the middle of the fifth whorl they become closer, and 

 from there to the last whorl they are close, straight and strong, and 

 the whorls are only slightly convex. The last whorl, in dorsal view, 

 is decidedly narrower, straight-sided, the base convex, indistinctly 

 angular at junction of lateral and basal surfaces. The back of the 

 last whorl has few, widely separated ribs, alternating with short ones 

 below the suture. Last whorl solute, shortly free. Aperture 

 quadrate-rounded, the peristome continuous, free, white, broadly 

 expanded and reflected. Superior lamella low, not attaining the 

 margin, widely separated from the spiral lamella ; inferior lamella low, 

 obliquely ascending, sigmoid, penetrating slightly deeper lhan the 

 spiral lamella, to the middle of the ventral face. Subcolumellar 

 lamella not visible in the aperture. Principal plica strong, con- 

 spicuous in the aperture, penetrating to a lateral position, approach- 

 ing close to the spiral lamella deep within. Lunella lateral, straight, 

 oblique, somewhat protractive, at the upper end terminating in an 

 ill-defined upper palatal nodule which is united by a callus with the 

 principal plica ; lower end of the lunella running into an oblique 

 lower palatal plica. 



Length 17.5, diam. in the middle 3.5 mm.; 10^ whorls. 



Length 15.25, diam. in the middle 3.4 mm.; 9^ whorls. 



The clausilium is narrow, parallel-sided, arcuate and twisted, in 

 transverse section v-shaped, much thickened along the longitudinal 

 convexity and at the distal end, which is obtusely rounded ; grad- 

 ually tapering into the filament above. PI. IV, figs. 1, '2. 



Malta. Cotvpes No. 108775 A. N. S. P. and in Mr. Emerson's 

 collection. 



