12 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



coluracllari ximbilicum versus late dilatato, callo tcmii labro juncto. 

 Diam. maj. 62 mm., min. 50 ; alt. 36. Apcrtura cum perist. 38 lata^ 

 28 alta. Var. — Testa omnino castaneo-rufa, ad carinam saturate 

 an<?uste zonata. ITub. — Annam. 



On examining the spire it will be observed tliat after the formation 

 of the two first whorls, there is a strong mark of arrested growth. 

 On the completion of each succeeding whorl there is a similar mark, 

 possibly indicating a season's growth. If this surmise be correct, it 

 would take four years for the animal to obtain its full dimensions. 



JI. granulifera, Mcillendorff , from China, has similar sculpture, but is 

 of a dilfcrent form, has a somewhat stronger keel and a less expanded 

 lip to the aperture. 



Amphidroxtjs costifee. 



Testa rimata, ovata, dextrorsa, solida, albida, supra anfract. ultimum 

 purpureo-fusco plus minus strigata vel variegata ; anfractus sex 

 convexiuscixli, sutura leviter obliqua sejuncti, lineis incrementi (in 

 anfr. ult. rugosis) striati, striis spiralibiis obsoletis sculpti, ultimus a 

 tcrgo varice albo perobliquo valido instructus ; apcrtura late subauri- 

 formis, longit. totius ^ ada?quans, intus albida ; peristoma album, 

 incrassatum, margine dextro leviter reflexo, columellari late dilatato, 

 superne callo albo crasso latissimo labro juncto ; columella sub- 

 perpendicularis, leviter contorta : spira conoidea, marginibus convexis. 

 Longit. 47 mm., diam. 24. Apertura intus 21 longa, 13^ lata. 

 Sab. — xlnnam. 



Amphidromus costtfer, n.sp. 



This species is remarkable for its short ovate form, the somewhat 

 rugose lines of growth, and its irregular auriform aperture ; but 

 especially for the varix or former lip on the back of the body-whorl. 

 This apparently indicates a period of arrested growth, probably of the 

 previous year. It occurs in all the specimens as yet known, seven in 

 number, with the exception of one of immature growth. This is in 

 nice fresh condition and shows that the colour of the species is much 

 brighter in the young shells. Beneath the suture the whorls are faintly 

 margined with pale yellow, and, between the varix on the back of the 

 last whorl and the lip, the surface is whitish, the pui-ple-brown 

 markings which occur on the rest of the whorl ceasing at the varix. 

 This species sometimes attains larger dimensions than those given 

 above, the finest specimen having a length of 54 millim. 



