226 



3. Nematura poLiTA, Sowcrby. N. testd magnd, castaneo- 

 fuscd, compressd, subvaricosd ; aperturd ovali, peritremate mi- 



tic^ striata ; regione umbilicali lird callosd circumdato ; punc- 

 tato-striatd. 

 Mus. Cuming. 



4. Nematura olivacea, A. Adams. N. testd ovatd, opacd, 

 olivaced, viridi-fusco reticulatd; aperturd ovali, spird elevatd, 

 apice decollato, peritremate simplici. 



Mus. Cuming. 



5. Nematura glabrata, A. Adams. N. testd magnd, ovatd, 

 non compressd aut varicosd, suhviridi-corned ; spird acuta, 

 apice acmninato, Icevi, politd ; aperturd orbiculari, angustatd, 

 peritremate nigro. 



Hah. Penang. Mus. Cuming. 



6. Nematura puncticulata, A. Adams. iV. testd mediocri, 

 pallide fulvd, compressd, anfractu ultimo gibboso, et subangu- 

 lato ad latera, lineolis punctatis transversis ornatd, peritre- 

 mate simplici. 



Hab. Eastern Islands. Mus. Cuming. 



8. A Monograph of the recent species of Rimula, a genus 



OF Mollusca, belonging to the family FiSSURELLIDjE. 



By Arthur Adams, R.N., F.L.S. etc. 



The genus Rimula of Defrance has been usually confounded with 

 Puncturella of Lowe, or the Cemoria of Leach, but it is at once 

 distinguished by the absence of the arcuated plate in the interior of 

 the vertex. The species already known are fossil, to which we now 

 add a few recent examples. 



Genus Rimula, Defrance. 



Shell conical, with an elevated, recurved, entire vertex, turned 

 towards the posterior end ; surface cancellated, with radiating ribs ; 

 a linear perforation in the upper part of the shell, half-way between 

 the vertex and anterior margin ; margin of aperture crenulated ; in- 

 terior simple, with no shelly plate ; muscular impression crescentic, 

 interrupted in front. 



1, Rimula exquisita, A. Adams. R. testd magnd, ovali, semi- 

 pellucidd, albd, costis longitudinalibus, radiantibus, lineisque 

 elevatis, transversis, concentricis, cancellatd; cancelli subqua- 

 drati ; costis crenulatis, incequalibus, prominentibus, anterio- 

 ribus duabus divergentibus, intei'stitiis costellis duabus in- 

 structis ; supra perforationem concavd ; perforatione elongatd 

 subquadratd. 

 Hah. Catanuan, island of Luzon and island of Burias, found on 

 dead shells, 7 and 10 fathoms, sandy mud {H. C). Mus. Cuming. 



