248 HELIX-CHLORIT1S. 



Group of H. unguicula. 



Spire plane, neither sunken or convex , unicolored or with one 

 or two light bands. Distribution, Moluccas. 



H. UNGUICULASTRA Martens. PI. 50, figs. 39, 40, 41. 



Shell discoidal, narrowly umbilicated, lightly, widely striate^little 

 shining, chestnut colored, unicolored ; spire plane, suture rather 

 deep ; whorls 5, the last tumid, rounded, convex beneath. Aperture 

 little oblique; broadly lunar; peristome scarcely thickened, all 

 around shortly and equally expanded, violaceous. (Ms.) 



Amboyna group of the Moluccas, Is. of Burn and Amboyna. 



H. unguiculastra MART. Preuss. Exped. Ostas. Landschu., p. 281, 

 t. 14,f.l. 



Von Martens recognizes two forms : 



a. var. Buruensis (or typical ; see figs.) 



Larger, last whorl obtusely angled at suture, but little and 

 gradually descending in front ; umbilicus narrower. Alt. 14, greater 

 diam. 26, lesser 22; length of apert. 15, width 14 mill. Alt. 11, 

 greater diam. 22?, lesser 18 ; length of apert. 12, width 12 mill. 



b. var. amboinensis Mts. Smaller, last whorl scarcely angular, 

 deeply descending in front ; umbilicus a 1 ittle wider. Alt. 1 1 , greater 

 diam. 22, lesser 18 mill.; apert. length Hi, width 10 mill. Alt. 9, 

 greater diam. 18, lesser 14? mill. ; apert., length 9, width 9 mill. 



Animal dark reddish-gray, finely granulate ; tentacles slender, 

 black ; tail smooth, without mucous gland ; sole 26 mill, long, 6 

 broad ; tentacles 13 mill, long; jaw with projecting riblets [leisten]. 

 Very shy. Young, fresh examples are finely hairy. (Martens.') 



This species resembles in color and the narrow umbilicus H. un- 

 gulina; In the flattened form and the entirely flat spire it is more 

 like unguicula; but it is smaller than either. The far flatter form, 

 quite comparable to H. quimperiana, renders the smaller forms quite 

 different from H. quieta Kve. The H. flexuosa of Pfeiffer may be 

 the same. Martens believes the locality " Borneo ", given by Pfeiffer 

 for that species, to be an error for Burn. 



Var. PILOSA Martens. Shell inflated-discoidal, moderately um- 

 bilicated, lightly striatulate, beset ivith short black hairs ; pale brown ; 

 spire plane, suture moderately deep ; no angle at the suture, whorls 

 5, the last inflated, rotund, deeply deflexed in front ; aperture sub- 

 diagonal, lunate-circular, peristome not thickened, all around ex- 

 panded, reflexed, white. Alt. 11, greater diam. 21, lesser 17? mill.; 

 apert. alt. 10*, diam. 11 2 mill. (Mart.) 



