iEGISTA. 



219 



ascending, triangularly dilated, scarcely reflexed over the um- 

 bilicus, which is funiculate and u^.oderately wide, exhibiting the 

 whole of the penultimate whorl. Major diam. 15-17, minor 13-5- 



penu 

 15 mm. ; alt. 7*25-9 mm 



189. JEgista catostoma, Blanford. 



Helix {Trarhiu) catostoma, Blanford, P. Z. S. 1869, p. 447 ; Haiiley 



& Theobald, Conch. Ind. 1870, pi. 56, figs. 2, 3. ^ 

 Helix (Plec/otropis) catostoma, Nevill in Anderson, Zool.Hes.Two 



Exped. West. Yunnan, i, 1878, p. 878 ; ibid.. Hand List, i, 1878, 



p. 73. 

 Helix (Plectotroins [Atgista)) catostoma, Tryon, Man. Conch, ser. 2, 



iv, 1888, p. 62, pi. 13, figs. 36, 37. . 



Eulota {Plectotropis) catostoma, Pilsbry, IMan. Conch, ser. 2, ix, 



1895, p. 209. 



Original description •.—^' Test^i late umbilicata, depressa, sub- 

 discoidea, cornea, tenuis, striata. Spira depresso-convexa, sutura 

 leviter impressa. Autr. 7, convexi, arete convoluti, ultimus 

 rotundatus, circa urabilicum subcompressus, antice abrupte de- 

 flexus, valde descendeus, pone aperturam subconstrictus. Apertura 

 fere horizontalis, truncato-ovata ; peristoma album, reflexum, 

 antice et postice prope anfractum penultimatum arcuatum, mar- 

 ginibus subdistanter convergentibus, callo tenui junctis ; umbilicus 

 latissimus pervius." (Blanford.) 



Maj. diam. 16-18, min. 14-5-16, alt. 8-5-9'5 mm. 



Hah. India: Dihing, Khasi Hills ((?oc^m'n-^«s<en) ; Naga Hills 

 {Chennell). Burma : Bhamo {Hunger ford). China : Ponsee, 

 Yunnan (Anderson). 



Blanford called it a peculiar form, resembling H. oldhami, but 

 Avith the mouth somewhat as in ff. nilagirica. In contour it 

 certainly somewhat assimilates with the former, but the mouth I 

 consider more hke that of atkinsoni. The last whorl suddenly 

 and deeply descends in front, the superior margin of the peristome 

 is sinuous in outline, projecting forward in the middle. In a 

 specimen I received from the late Col. Beddome the base of the 

 last whorl is decidedly flattened for a short distance behind the 

 peristome and the basal margin is accordingly almost straight, with 

 a dentiform callus on the inner side. Mr. Ponsonby possesses a 

 similar specimen also received from Col. Beddome, and both agree 

 well with the figure in Conch. Ind. in this respect as they do in 

 size, the major diameter being only 13-5 mm. The junction of 

 the basal and columellar margins forms nearly a right angle and 

 the aperture may in fact be called subquadrate. Two specimens 

 in the Britisli Museum, however, collected by Hungerford at 

 Bhamo, do not possess the flattened base, nor the denticle on the 

 basal margin of the peristome, but have the mouth gibbous behind 

 tlie peristome. These distinctly show spiral strite below the 

 periostracum, regular above and irregular below the periphery, 



