10 



ORCULA. 



Species of Asia and Africa. 



Peristome reflected (10) 



Peristome from slightly to well expanded, more or less 

 thickened within (13) 



f Perforate, compressed around the base; aperture an- 

 gular below, parietal callus very strong ; 10 x 4 mm. 

 1 0. robust a, no. 11 



I Imperforate; not angular basally ; smaller (11) 



Having spaced epidermal riblets when well preserved ; 

 no palatal fold within; 4.5 to 6.5 mm. long (12) 



Finely striate without spaced riblets; lip strongly cal- 

 loused within ; a very deeply immersed palatal fold. 

 0. s. batumensis and allies, no. 12d 



{ Early whorls conspicuously convex, overhanging the 

 19 I suture. Abyssinia. 0. imbricata, no. 7 



j Whorls moderately convex. Smyrna, Alexandria. 



O. d. turcica, no. 6b 



13, 



11 



Small, 2.5 to 6 mm. long; less than 3 wide; lamelhe 

 enormously enlarged within ; shell sometimes bristly. 

 O. raymondi and varieties, no. 14 

 I Larger, 7-12 mm. long, 3-5 wide (14) 



u{ 



Broad, diam. about 4.5 to 5 mm. (15) 

 Narrower, diam. about 3 to 3.5 mm. (16) 



A long, immersed lower-palatal fold. Aleppo. 



O. moussoni, no. 13 

 j No palatal fold (in forms examined). Cyprus, Syria. 



0. sirianocoriensis and varieties, no. 10 



Sinistral ; 7.5 x 3.5 mm. Adana, Cilicia. 

 16 -j 0. s. heterostropha, no. 12a 



Dextral (17) 



