. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. Fig. 7. Radulae of: a. Daphnella (?) sulcicancellata (Brnrd). b. D. alfredensis Bartsch. 'Pleurotoma' curricula Fig. 8 Description: Shell thin. Protoconch i\ or 2 whorls, corroded. Post-natal whorls 4; 1 st corroded; 2nd, 3rd and 4th with a narrow cingulum projecting beyond the incised suture; about 22-34 axial pliculae (or enlarged growth-lines), strongly sigmoid, concave in sulcus, protractive below, each plicula forming a small point on the cingulum; pliculae evanescent on base. On 2nd and 3
. Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum. Natural history. Fig. 7. Radulae of: a. Daphnella (?) sulcicancellata (Brnrd). b. D. alfredensis Bartsch. 'Pleurotoma' curricula Fig. 8 Description: Shell thin. Protoconch i\ or 2 whorls, corroded. Post-natal whorls 4; 1 st corroded; 2nd, 3rd and 4th with a narrow cingulum projecting beyond the incised suture; about 22-34 axial pliculae (or enlarged growth-lines), strongly sigmoid, concave in sulcus, protractive below, each plicula forming a small point on the cingulum; pliculae evanescent on base. On 2nd and 3rd whorls 5, on 4th whorl 6 spiral grooves often crossing the pliculae, but more distinct between them; about 15 grooves on base. Sinus in profile straight; a slight shoulder where the pliculae become protractive. Shell 8-5 X 3 • 75 mm. White, somewhat translucent. Locality: 340 36' S. 170 00' E., 1500-1760 fathoms. One dead but fresh, 2 broken. Type: A9859. Remarks: There is a superficial resemblance to Pleurotoma truncata Schepman, 1913, and Drillia rubidofusca Schepman, 1913, both of which have a narrow cingulum; but both of them have axial ribs, at least on the earlier whorls, whereas in the present specimens the axial sculpture consists of enlarged growth-lines, which at most form pliculae and can scarcely be called ribs. Pleurotomella ida Thiele, 1925 Pleurotomella ida Thiele, 1925: 230, pi. 40, fig. 21. Description: Aperture subequal to spire. Protoconch 3 whorls, altitude and diameter 0-5 mm, with criss-cross sculpture. Post-natal whorls 5. Axial ribs 10 on 1st and 2nd whorls, 11 on 3rd and 4th, 12 on 5th, crossing sulcus and continued on base; crossed by 2 spiral lirae, intersections rather sharply nodulose; on 3rd and following whorls a fine lira between the 2 main ones, on 4th another fine lira between lower main lira and suture; on base about 12 lirae, the uppermost one (at top of aperture) the strongest. Canal longer than in Thiele's figure. Lip sinus adjo
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectnaturalhistory, booky
