PLEUROTOMA. 



Plate VI. 



Species 38. (Mus. Cuming.) 



Pleurotoma discors. Pleur. testa turritd, fused; an- 

 fractibus superne prope suturam unicarinatis, inferne 

 nodtilosis, medium' lavibus ; anfractu ultimo trans- 

 versim lineato, varice conspicuo ; aperturd brevi, 

 ovatd, labro profundi emarginato . 



The discordant Pleurotoma. Shell turrited, blackish 

 brown ; whorls encircled with a single keel round 

 the upper part, nodulous round the lower part, and 

 smooth round the middle ; last whorl transversely 

 lineated, and has a rather prominent lump or varix ; 

 aperture short, ovate, lip deeply emarginated. 



Sowerby, Pro. Zool. Soc, 1833, p. 137. 



Reeve, Conch. Syst, vol. ii. pi. 234. f. 10. 



Hab. Island of Plata, West Columbia (dredged from 

 coral sand at the depth of seventeen fathoms) ; 

 Cuming. 



The specimen here figured is the only one that has 

 been seen, and is therefore at present unique in the 

 collection of Mr. Cumins;. 



Species 39. (Mus. Cuming.) 

 Pleurotoma zonulata. Pleur. testd crassd, subcylin- 

 dricd, nigerrimd; anfractibus superne lira, medicine 

 cingulo flavo monilifero ornatis ; anfractu ultimo liris 

 cingulisque duobus ; canali brevissimo. 

 The little-belted Pleurotoma. Shell thick, cylin- 

 drical, jet-black ; whorls ornamented round the 

 upper part with a small ridge, round the middle 

 with a bright yellow-beaded belt ; last whorl show- 

 ing two ridges and two belts ; canal very short. 

 Reeve, Conch. Syst., vol. ii. pi. 234. f. 10. 



Pleurotoma cincta, Sowerby (not of Lamarck), Pro. 



Zool. Soc., 1833, p. 136. 



Hab. Monte Christi and Xipixapi, Central America 



(found in sand and gravel at a depth of seven 



fathoms) ; Cuming. 



Each whorl in this species is encircled with two fine 



ridges and two yellow-beaded belts, but one of each of 



these becomes hidden during the growth of the shell by 



the deposit of one whorl upon the lower half of the other. 



Species 40. (Mus. Cuming.) 

 Pleurotoma bicolor. Pleur. testd oblongd, pyramidali, 



fused ; anfractibus superne concavis, inferne lonrji/u- 

 dinaliter costatis, costisftavidis, postice tuberculiferis ; 

 canali brevissimo. 



The two-coloured Pleurotoma. Shell oblong, pyra- 

 midal, blackish brown ; whorls concave round the 

 upper portion, lower portion longitudinally ribbed, 

 ribs yellow and tuberculated posteriorly ; canal 

 very short. 



Sowerby, Pro. Zool. Soc, 1833, p. 135. 



Hab. Panama and Gallapagos Islands (found under 

 stones at the former place, in sand at the depth of 

 eight fathoms in the latter) ; Cuming. 



Care must he taken not to confound this species with 

 the PI. zebra which is always of reddish colour and more 

 sharply turrited. 



Species 41. (Mus. Cuming.) 



Pleurotoma pyramidata. Pleur. testd ucutissim'e py- 

 ramidali, fused; anfractibus superne cingulo a/bido 

 monilifero decurrente, mediane tumidis, eleganter pli- 

 catis, plicis albis, in serie regular! dispositis ; canali 

 brevissimo, subrecurvo. 



The pyramidal Pleurotoma. Shell very sharply py- 

 ramidal, blackish brown ; whorls with a small 

 white-beaded band round the upper part, the 

 middle part being swollen and elegantly plaited, 

 plaits white, and arranged with great regularity ; 

 canal very short, and a little recurved. 



Valenciennes, MSS. (Paris Museum.) 



Kiener, Icon., pi. 21. f. 3. 



Hab. Coast of Senegal, and the Gambia. 



The figure which Kiener refers to in the ' Encyclo- 

 pedic Methodique ' cannot have been intended to re- 

 present this shell. 



Species 42. (Mus. Belcher.) 



Pleurotoma unimaculata. Pleur. testd turritd, acumi- 

 nata, albd, anfraclus ultimi dorso fusco-macula/d ; 

 anfractibus medio tuber culatis, tuberculis in costel/as 

 interdum confluentibus ; aperturd brevi, labro expanso, 

 profundi' sinualo ; canali brevi, recurvo. 



The single-spotted Pleurotoma. Shell turrited, 

 acuminated, white, back of the last whorl being 



Feb. 1843. 



