MUREX. 



Plate XIII. 



Species 50. (Fig. a and b, Mus. Said.) 



MuKEX HUMILIS. Mur. (estd ovato-pi/riformi, spird brevi, 

 angulato-turritd, anfractibus mperne planulatis, infra 

 contractis, transversim liratis, Uris pojie varices conspi- 

 cuis ; octofarlam varicosd, varicibus medio seriatim du- 

 plieato-squmnatis, squatnis brevibus, recurvis, basifron- 

 dosis,frondibus subramosis, spiuosis ; albido-fuscescente, 

 aurautio-riifesceidK profuse tinctd et nmciilatd; aper- 

 tiird parvd ; caiiali subdonyatd. 



The humble Murex. Shell ovately pyi'ifonn, spire short, 

 angularly tuiTeted, whorls depressed round the upper 

 part., contracted below, transversely ridged, ridges 

 conspicuous behind the varices ; eight-varicose, vari- 

 ces consisting in the middle of a double row of scales, 

 pecidiarly ciu-ved back, at the base of a single row of 

 slightly branched spinous fronds ; whitish brown, pro- 

 fusely stained and spotted with orange red ; aperture 

 small, canal slightly elongated. 



Broderip, Pro. Zool. Soc, 1832 ; Sowerby, Couch. lUus. 

 f. 4G and 47. 



Uab. St. Elena, western coast of South America (dredged 

 from sandy mud at the depth of seven fathoms) ; 

 Cuming. 



Tliis species has been but imperfectly described and 

 figured hitherto for want of a good specimen. It is a species 

 of very peculiar character, its pyi'iform growth, the curi- 

 ously reciu-ved bi-squamate struetiu'e of the varices, and its 

 orange-red coloLU'ing are featm'es of considerable specific 

 interest. 



Species 51. (Mus. Said.) 



Murex ambiguus. Mur. testa globosd, subpyriformi, trnns- 

 versim liratd, Uris irrei/ularibus, iuttrruptis ; octofa- 

 riam varicosd, varicibus frondosis, fromlibns alteniis 

 vel pauciorihus elato-raniosis, spinosis, basalibus louyi- 

 oribus ; alba, frondibus lirisque aterrimis, labri colu- 

 mellari parte superiord nigra tinctd; canali breviusculo. 



The ambiguous Murex. Shell globose, slightly pyi'i- 

 form, transversely ridged, ridges ii-regidar, interrupted; 

 eight-varicose, varices frondose, the alternate fronds, 

 or fewer, elevately branched, spinous, basal fronds 

 longer ; white, fronds and ridges jet black, upper part 



of the columeUar lip stained with black ; canal rather 



short. 

 Reeve, Pro. Zool. Soc, 1845. 

 Hab. ? 



Tlu-ee species appear to me to have been confused hi- 

 therto under the common title of Murex radix, which 

 though closely approximating may be sepai-ated without 

 difficidty by any person possessing a tolerable share of con- 

 chological discrimination. The trae Murex radix is a 

 round particularly solid heavy shell with a short, though 

 sharply acuminated, spire, with not less than ten varices, 

 in which the fi'onds are nmnerous, somewhat laterally com- 

 pressed, comparatively short, and sharp pointed ; the spe- 

 cies described by Dr. PhQippi under the title of Murex 

 nigritus (for which see PI. 13. Sp. 47), has but eight or 

 nine varices and the fronds are not branched, those on the 

 upper angle of the whorls being tubercularly squamate, 

 those in the middle flat and very obscure, whilst those at 

 the base are long and horn-shaped. In the species under 

 consideration the shell is of somewhat light structm-e and 

 the fronds are large, open, and flowery. It certainly pre- 

 sents a modification of character intermediate between the 

 Murices radix and nigritus, but it is always easy to be 

 distinguished ; and any modification of structiu'c may, I 

 apprehend, be considered of specific importance when it is 

 not iimnediately approached on either side. 



Species 52. (Mus. Metcalfe.) 



Murex corrugatus. Mur. testd ovato-fusiformi, inter 

 varices bituberculatd, transversim liratd et striata, Uris 

 subconspicuis, obsolete nodosis ; trifariam varicosd, va- 

 ricibus obliquis, peculiariter laminato-squamatis ; fer- 

 rugineo-fuscd, apertura fance violaced. 



The wrinkled Murex. Shell ovately fusiform, with 

 two tubercles between the varices, transversely ridged 

 and striated, ridges somewhat conspicuous, obsoletely 

 nodided; three-varicose, varices oblique, peculiarly 

 laminately squamate ; rusty-brown, interior of the 

 apertm-e tinged with violet. 



Sowerby, Pro. Zool. Soc, 1840. 



Hab. North Australia ; H.M.S. Beagle. 



This shell has very much the aspect of the Murex pal- 

 miferus, the varices are nevertheless of very difi'erent struc- 



Jmie 1845. 



