SOPniXA. — HEMIPLECTA. 289 



or slioi't close cleft forming a very sharp keel, continuous up the 

 umbilicus. 



Size specimen figured : major diam, 8, min. 7*5, alt. 4 mm. 



Large spec, in Brit. Mus. : „ „ 9, „ 8-5, „ 4 „ 



Ilah. Damotha, near Moulmein. Figured specimen from the 

 Godwin-Austen collection : received fx*om Stoliczka. 



This species may be known from all others of this genus by 

 the coarse spiral striation on the basal side.] 



[458. Sophina forabilis, var. bensoni. Vide fig. 87, E, E'. 



Shell globosely conoid, uiiibilicated ; surface smooth, not polished ; 

 colour umber-brown ; spire depressedly conoid, suture impressed ; 

 whorls 5, increasing regularly, the last two rather more rapidly, 

 rounded on the periphery; aperture ovately lunate, oblique, 

 columellar margin subvertical, very slightly thickened, forming a 

 sharp angle with the peristome, but no notch, the angle continued 

 perspectively as a blunt keel within the umbilicus. 



Size: major diam. 7*5, min. 6-5, height axis 4 mm. 



Hah. Damotha, near Moulmein (Sioliczka). 



Three specimens of this shell received by me from Eerd. Stoliczka 

 in the same tube with >S^. forabilis, but the absence of striation in 

 the umbilical region and the different form of umbilical keel are 

 sufficient to distinguish the species. It is very close to S. conjungens, 

 but much smaller. Several examples named forabilis in the British 

 Museum collection agree with this form.] 



Genus HEMIPLECTA. 



Hemiplecta, Alters, Reliceen, 1850, p. GO; Godwin-Austen, Mol. 

 hid. ii, 1898, p. 70. 



Type, H. humplireysiana. Lea, from Singapore. [Fig. 88, A-D.] 



Range. Burma, Siam, the Malay Peninsula and part of the 

 Malay Archipelago. Species from the peninsula of India formerly 

 referred to this genus are now known to belong to Ariophanta. 



Shell perforate or umbilicated, subterminate or depressed, rather 

 sohd; whorls regularly increasing; aperture lunate; peristome 

 obtuse, sometimes more or less thickened. 



Animal with both right and left shell-lobes developed, but small ; 

 dorsal lobes large, the left divided into two parts. ^Mucous pore 

 large, sometimes with an overhanging lobe above. Foot divided 

 longitudinally beneath. 



In the generative organs the dart-sac is very large and cylin- 

 drical, the spermatheca small and pear-shaped ; the retracted 

 muscle of the penis attached at about two-thirds of the length from 

 the distal extremity to the junction of the vas deferens, without 

 any free caecum. jSTo kale-sac. 



Kadula long and broad, with many teeth in a row. In 

 H. humplireysiana Godwin- Austen found 1653 rows, each contain- 

 ing 125 . 2 . 20 . 1 . 20 . 2 . 125 (147 . 1 . 147) teeth. The 



