310 MELYILL AND STANDEN : SHELLS FROM LIFU. 



columella white. We have this species also from Thursday- 

 Island. What appears to be another form of the same shell is 

 also in the collection, with darker ochraceous spiral lines across 

 the two last whorls, the longitudinal costse obscure, and here 

 and there wanting, apical whorls dark-brown. 



Rissoia pyrrhacme sp. nov. (PI. XL, fig. 70). 



R. testa oblonga, delicatula, nivea, a nfra dibits novem(interdum 

 odd), quorum apicalibm tribus, fulvo-ochraceis, aiteris albis, 

 ventricosis, ad suturas crenulato-impressis, longitudinaliter 

 costulatis, spiraliter arete su/at/osis, apertura rotuudo-ovata, 

 labro simp/ice, paulhiliiin effuso. 



Long., 6, Lat., 2 mill. 



A pure white ochre-tipped shell, whorls eight or nine, 

 much swollen, longitudinally ribbed, spirally closely sulcate, 

 aperture round, lip simple, a little effuse. We are not yet 

 quite sure of the proper location of this and the preceding 

 species, and only place them provisionally in -Rissoia. If, 

 indeed, they be Rissoia, they will, perhaps, be better included 

 in a new section of the genus. Several specimens. (irvppo% 

 ochre red, a«p; point). 



Mathilda eurytima sp. nov. (PI. XL, fig. 73). 



M. testa delicata, pyramidato-fusiformi, alba, anfrarfibus 

 decern, ventricosis, ad suturas impressis, spiraliter acute tri- 

 carinatis, carinis angulatis, interstitiis longitudinaliter clath- 

 ratulis, clathris ardis, sub lente concinnis, ultimo anfradu 

 quadricarinato, basi tortiata, apertura ovato-rotunda. labro 

 simplice, canali produdo. 



Long, 6, Lat., 2 mill. 



A most delicately lovely, though minute shell. A second 

 specimen having occurred, the first, named provisionally 

 M. sinensis by us in our last paper, has been carefully re-ex- 

 amined and found to be distinct from that species. The 

 spiral keels are only three on the upper whorls, as against 

 four in M. sinensis, the shell is not of thickened texture, and the 



J.C., viii., Oct., 1S96. 



