480 Zoological Society, 



meant to be represented in fig. 69 of the * Conchological Illustrations/ 

 which is mentioned as a variety of M. Motacilla, though there are 

 still some little points of difference. A fine specimen often permits 

 a conchologist to clear up his doubts as to specific importance, and 

 I have had the assistance of such in drawing up the above descrip- 

 tion. Indifferent specimens are not uncommon, and Mr. Sowerby, 

 jun. had most probably only such, and was compelled to leave it as 

 a variety of M. Motacilla. 



MuREX CENTRIFUGA. Muv. tcstd gracHUme fusifovmi, pallide cor- 

 ned, passim creberrim^ striatd ; varicihus tribus, subalatis, in spi- 

 nis compressis laciniatis ; spind ad angulum anfractuum elongatd, 

 subrectd ; interstitiis nodo unico ; aperturd elongatd, ovali ; labro 

 intiis Icevi ; canali mediocri, rectiusculo, clause, ad basin subre- 

 curvo. Axis 16 lin. 

 Hab. West coast of Veragua ; on a sandy floor in fifty-two fathoms. 

 This species has the general character of M. pinniger and M. ca- 

 pensis, and is very closely allied to the latter. 



MuREX FESTivus. Mur.testdfusiformi, crassd, fulvd, trivaricosd; 

 varicibus simplicibus, recurvis, superne cristatis, subtilissime cre~ 

 niferis ; interstitiis nodulosis, lineis subgeminis transversis fuscis 

 eleganter ornatis ; aperturd ovali ; labro intiis sparslm denticulate ; 

 canali valde clause, ad basin subrecurve. Axis 13 lin. 

 Hab. Bay of Madalena, California ; dredged from seven fathoms, 

 on a sandy floor. 



MuREx FOVEOLATUS. Mur. tcstd fusiformi, crassd, multivaricosd, 

 transversim creberrime sulcatd, laminis minimis longitudinalibus 

 feveelatd atre-purpuree pallide bifasciatd ; varicibus septenis sim- 

 plicibus, pestice rotundatis, antice margine acutd ; aperturd ovali, 

 coarctatd ; labro intiis obtuse denticulate ; labio interne producto ; 

 canali aperte, subrecurve. Axis 12| lin. 

 Hab. Bay of Madalena, California ; with the preceding. 

 MuREX ANANAS. Mur. tcstd fusiformi, ventricesd, crassd, multi- 

 varicosd ; anfractibus septenis superne subplanulatis, transversim 

 costatis, costis alternate mineribus; varicibus senis rotundatis 

 spiniferis, spird supremd prcecipue maximd, brevi, rectd, selidd, 

 biplicatd, transversim cempressd, cceteris brevissimis subcequali- 

 bus; aperturd rosed, rotundatd, seu paulisper elongate ovali, pestice 

 canaliculatd ; canali mediocri, subeblique, aperte, margine columel- 

 lari rugulesd, dorse bifariam spinoso, serie supremd superante. 

 Hab. West coast of Africa. Mus. Cuming. 

 A shell closely resembling M. rosarium in its size and proportions, 

 but finds its specific distinction in its greater massiveness, the superior 

 size of its upper series of spines, and the absence of nodules on the 

 interstitial ribs. Both shells have a distinct fasciation of three dark 

 bands, but our species is entirely wanting in that beautiful and ele- 

 gant covering of striae which is so conspicuous in the fine specimen 

 of M. rosarium in Mr. Cuming's collection. 



MuREx Belcheri. Mur. testd magnd, fusiformi, crassd, penderosd, 

 pallide fused, multivaricosd ; anfractibus quadratis, albe fascia* 



