■»"•» 



ither ones with rather coarse, slightly < »1 .] i< | n< ■ ribs, which are aol crowded 

 the suture. 



truncata n. sp. PI. XXVI, fig. i. 



i M. Solid bluish grey mud with foraminifera, 



red by a 5 cM. thick layer of brown mud. 4 S| 



Shell shortly fusiform, very thin, whitish under a yellowish epidermis. Upper whorls 

 wanting bj erosion, remaining whorls 5, angularly convex, separated by .1 conspicuous undulated 

 suture; upper part of whorls concave, lower part slightly convex, sculpture consisting of strongly 

 ed ribs, more conspicuous in upper whorls, becoming fainter in last one, where they nearly 

 disappear and have more the character of strong growth-lines below the periphery; on the 

 upper whorls these ribs form tuberclès on the fasciole, becoming more foldlike on the lower 



the whorls are crossed by numerous spirals, forming a subsutural rib, which on upper 

 whorls is more conspicuous and adorned with small beads, corresponding to the upper ends 01 

 the ribs, the excavation and fasciole are finely lirate; on the basal half of each whorl, the lirae 

 are coat pecially on last whorl, where they are irregular, with some intermediate ones. 



Last whorl strongly contracted below periphery, ending in a short, wide canal, slightly directed 

 to the left. Aperture oval, with a moderately sharp angle above and a very wide but not deep 

 sinus at the periphery; peristome thin; columellar margin with a conspicuous white layer of 

 enamel. Operculum thin, corncous, with basal nucleus. 



Alt. 10. lat. S: apert. alt. 9, lat. ;, ! , Mill. 



This remarkable species is more or less variablc in sculpture, as far as concerns the 

 strength of ribs, tuberclès and spirals, but three of them agree in every important particular, 

 in the fourth, a young shell, some characters are obliterated. rhough the species may belong 

 to the alliance of /'. praesignis Smith and rotatilis v. Marts., it is impossible to combine it 

 with any of the described species. 



19, Pleurotoma (Gemmula) Sibogae n. sp. PI. XXVI, fig. 2. 



t. 157. Channel between Makjan and Halmahera. 472 M. Fine dark muddy -and. 1 S 



Shell broadly fusiform, with acute, conical spire and strong, angular last whorl, thin, 



whitish. faintly yellowish on the keel, between the nodules. Whorls 11, bul the number may 



be considerably more. as the upper nuclear whorl seems to be wanting and the shell bas the 



arance of being not adult. One upper nuclear whorl (or 2) smooth, convex, foliowed by 



'v another whorl, with rather remote ribs; subsequent whorls concave above the keel, with 



a m ly strong infrasutural keel and 1 or 2 other spirals in the excavation between suture 



and keil; the infrasutural keel becomes fainter and is scarcely if at all traceable on lower 



re on the contrary the number of spirals increases, so that on last whorl of the 



•1 their number amounts to h and two very narrow one. jusl above the keel; this latter 



narrow, composed of 3 narrow superficial spirals, more conspicuous between the nodules, 



40 



