PLEUROTOMA. 



Plate XIX. 



(Eight of the following species were dredged during the surveying voyage of H.M.S. Beacon, Capt. Graves, amongst the islands 

 of the Grecian Archipelago, in 1841 ; the figures of them are considerably magnified.) 



Species 156. (Mus. Forbes.) 



Pleurotoma cwspata. Pleur. teskt fnsiformi-turritd, 

 anfractibus convexis, carinis tribus prominentibus 

 cinctis, interstitiis latiusculis, striis longitudinalibus 

 obliquis eleganter sculptis, carinis anfracliis ultimi 

 subtilioribus, numerosis ; alba, apice fuscescente 

 tincto ; canali brevissimo, columelld perforatd. 



The curled Pleurotoma. Shell fusiformty turreted, 

 whorls convex, encircled with three prominent keels, 

 the interstices between which are broad and ele- 

 gantly sculptured with oblique longitudinal striae, 

 keels of the last whorl finer and numerous ; white, 

 apex stained with light brown ; canal very short, 

 columella perforated. 



De Cristoforis and Jan, Cat. No. 29. 



Philippi, Enum. mol. Sicil., p. 200. 



Hab. Mediterranean (found at the depth of from forty to 

 a hundred fathoms) ; Forbes. 



A species of great interest, on account of its having 

 been only known hitherto in a fossil state. 



Species 157. (Mus. Forbes.) 



Pleurotoma abyssicola. Pleur. testd brevi, conica, 

 nigricante-fnscd ; anfractibus tumidis, longitudinaliter 

 costatis ; cost is fort ibus, striis elevatis subdistantibus 

 deciissatis, canali brevissimo. 



The deep-dwelling Pleurotoma. Shell short, coni- 

 cal, blackish brown ; whorls swollen, longitudinally 

 ribbed ; ribs strong, crossed by rather distant raised 

 strise, canal very short. 



Forbes, Pro. Zool. Soc, 1S44. 



Hab. /Fgean Sea (dredged from the depth of a hundred 

 to a hundred and ten fathoms) ; Forbes. 



A small dark brown shell of very solid structure, in- 

 habiting a deeper zone in the ocean than any species we 

 have yet met with. 



Species 158. (Mus. Forbes.) 



Pleurotoma .minuta. Pleur. testd attenuutd, rubido- 

 fuscd, anfractibus longitudinaliter costatis, cost is for. 



tibus, striis elevatis subdistantibus decussatis ; canali 



brevi, recto. 

 The minute Pleurotoma. Shell attenuated, reddish 



brown, whorls longitudinally ribbed, ribs strong, 



crossed with rather distant raised striae ; canal 



short and straight. 

 Forbes, Pro. Zool. Soc, 1S44. 

 Hab. ^Egean Sea (dredged at the depth of from ninety 



to a hundred and five fathoms) ; Forbes. 



Species 159. (Mus. Macgillivray.) 



Pleurotoma decussata. Pleur. testd ovato-fusiformi, 

 lutescente-albd ; anfractibus convexis, striis elevatis 

 transversim et longitudinaliter decussatis, striis lon- 

 gitudinaUbiis anfracliis ultimi subirregularibus , nunc 

 confertis, nunc distantioribus ; labro simplici ; aper- 

 turd ampld ; canali brevi ; columelld subtortuosd. 



The decussated Pleurotoma. Shell ovately fusiform, 

 yellowish white ; whorls convex, crossed trans- 

 versely and longitudinally with raised stria?, the 

 longitudinal of which, upon the last whorl, are 

 somewhat irregular, sometimes close-set, sometimes 

 more distant ; lip simple ; aperture large ; canal 

 short ; columella rather twisted. 



Macgillivray, Moll. Aberdeen, p. 172. 

 Fusus decussatus, Brown. 



Hab. Coast of Aberdeen, North Britain (brought up from 

 deep water by a fishing-line) ; Macgillivray. 



I kindly thank Prof. Macgillivray for the loan of this 

 rare and interesting species. 



Species 160. (Mus. Forbes.) 



Pleurotoma Lyciaca. Pleur. testd subnbbreriato-fu- 

 siformi, anfractibus convexis, siiperne angustatis, 

 ultimo spirce sesquilougitudincm aqttante, longitudi- 

 naliter costatis, ti'ansversiiyi striatis, striis elevatis, 

 allirnis majusculis; aperturd lanceolato-ovatd ; canali 

 longiuscuto, recto. 



The Lyman Pleurotoma. Shell rather shortly fusi- 

 form, whorls convex, narrowed at the upper part, 

 last whorl as long, and half as long again, as the 



January 1844. 



