THE CONCHOLOGICAL MAGAZINE 



and expanded throughout. There are six teeth situated deep in the 

 throat, as follows : 



A high, compressed angulo-parietal lamella ; a thin entering 

 columellar lamella which descends slightly as it enters ; a minute 

 subcolumellar lamella ; a rather large upper palatal plica, and a 

 smaller, more deeply placed and basally situated lower palatal, with 

 a minute interpalatal plica between these two. 



Alt. 1.75, diam. 2.3 mm. 



Yonakunijima, Ryukyu. Cotypes no. 05.-52. A.N.S.P., and 

 no. 1,509 of Mr. Hirase's collection. 



This species resembles //. luzonicum Mldft, from near Manila, 

 in shape. It differs by the much smaller size, more numerous teeth, 

 and the more sinuous angulo-parietal tooth of the Ryukyuan species. 

 The very fine and delicate spiral stria; seem to be of cuticular sub- 

 stance. 



SUMMARY— ON JAPANESE MARINE MOLLUSCA (XX) 

 MITRID.L. 



Mitra episcopalis Linne. pi. xxxiii, fig. 131. 



Tryon, Man. Conch, vol. iv, p. 111, pi. 32, fig. 1. 



Jap. name, Chosen-fude Gum.-hin. 



Loc, Loo Choo and Oshima Islands. 

 Mitra papalis Linne. pi. xxxiv, fig. 133. 



Tryon, Man. Conch, vol. iv, p 11 1, pi. 32, fig. 2. 



Jap. name, Oni-kiba-fude n. n. 



Loc, Loo Choo Islands. 

 Mitra p07itificalis Lam. pi. xxxiv, fig. 134. 



Tryon, Man. Conch, vol. iv, p. 11 1, pi. 32, fig. 3. 



Jap. name, Nishiki-no-kiba Rop.-kai. 



Loc, ( )shima and Loo Choo Islands. 

 Mitra cardinalis Gmelin. pi. xxxiii, fig. 132. 



Tryon, Man. Conch, vol. iv, p. 11 1, pi. 32, fig. 4. 



Jap. name, Mam-fude-gai n. n. 



Loc, Loo Choo. 



