RUMINA. 215 



Subsp. DECOLLATA (L.). PL 53, fig. 70; pi. 55, fig. 99. 



The surface is malleated but scarcely decussate, there being 

 some spiral rows of vertical impressions only ; the size is mod- 

 erate, about 24 to 30 mm. long, the diam. generally exceeding 

 one-third the length. This is the form of southern France 

 (fig. 70), etc., and which has been spread by commerce in 

 the islands of the Atlantic and as far as America. The speci- 

 mens before me from the Canaries seem also to be of this 

 stock. Also the form of southern Spain (pi. 53, fig. 63, Ter- 

 ragona; after Kobelt) ; but var. decussata is also reported 

 from Spain. 



The anatomy of a specimen from Malta is figured; see 

 under the generic description. The count of teeth of the 

 radula varies, Fischer giving it as 50, 1, 50; Wiegmann as 

 42, 1, 42; and Binney as 38, 1, 38. The radula I examined 

 was frayed at the edges. 



Subsp. GRACILIS Pfr. PL 55, figs. 1, 2, 3. 



Shell corneous-brown or whitish-corneous, with the sculp- 

 ture of typical decollata, but small and very narrow, and 

 either cylindric or tapering. Whorls usually more numerous, 

 6-7. Length 20, diam. 8 mm. with 4 whorls; 27 x 8 mm. with 

 6 whorls (measurement to outer edge of lip). 



Greece (Patras, Athens, etc.), Crete (figs. 1, 3), Naxos, 

 Rhodes (fig. 2), Cyprus, Smyrna, and the Syrian coast gen- 

 erally. 



Bui. decollatus var. gracilis PFR., Mai. BL, iii, 1857, p. 177. 

 Smyrna (Bui. truncatus Ziegler in Mousson, according to 

 Pfr., 1. c.}. Not Bui. truncatus Brug. Bui. decollatus var. 

 minor Bgt., Malac. de 1'Algerie, ii, p. 6, pi. 1, f. 14, 15 

 (Smyrna), f. 16 (Algeria), f. 17 (Syria). 1864. 



This small, cylindric, Eastern race is apparently separated 

 from the typical decollata by an area without Rumina along 

 the western coast of the Adriatic. It is reported from several 

 Algerian localities by Bourguignat, but whether these shells 

 are another and parallel small race remains to be ascertained. 



