1904.] NATURAL SCIENCES OF PHILADELPHIA. 635 



outlines; apex obtuse. Whorls 5^, convex, slowly widening, the last 

 rounded at the periphery, convex beneath. Aperture crescentic; 

 columella arcuate, calloused within, the margin dilated and narrowly 

 re flexed above. 



Alt. 2.9, diam. 4 mm. 



Yakushima, Osumi. Types No. 87,558, A. N. S. P., from No. 1,282 

 of Mr. Hirase's collection. Also No. 1,282a from Kuchinoerabushima, 

 Osumi. 



This species closely imitates M. vaga, but it is readily distinguishable 

 by the rounded, not angular, last whorl. The whorls arc more closely 

 coiled than in M. tanegashimcB, and larger than M. yakuensis. Some 

 specimens from Matsubara-mura, Echizen (Mr. Hirase's No. 6066), 

 where M. vaga would be expected, seem to be M. lampra. 



This group of species is somewhat difficult. M. tanegashimce is a 

 larger species than M. yakuensis, more depressed than vaga or lampra, 

 with fewer whorls, the last one wider. M. yakuensis is probably iden- 

 tical with M. nuda, and both stand close to M. hilgendorfii Reinh.; but 

 that is described as whitish — " albida" — while the others are yellow or 

 amber colored. M. circumdata differs from all of the above species 

 in being spirally striate. 



MaorocMamys dulcis koshikijimana n. subsp. 



This form has the shape and microscopic spiral striation of M. dulcis 

 Pils., with the same number of whorls, but the spire is more elevated, 

 and viewed from above it is wider. 



Alt. 7, greater diam. 12, lesser 10.5 mm.; width of spire 7 mm. 



Shimo-Koshikijima, Satsuma. Types No. 87,521, A. N. S. P., from 

 No. 1,236 of Mr. Hirase's collection. 



In a specimen of M. dulcis of the same diameter the spire is a milli- 

 meter narrower. 



MaorocMamys subelimatus n. sp. 



Shell perforate, depressed, pale yellow, translucent, smooth and 

 glossy. Spire very low-conic. Whorls 4^, slowly increasing, the last 

 very wide, double the width of the preceding, rounded at the periphery 

 and base, indented around the perforation. Aperture slightly oblique, 

 lunate, the lip thin and simple, a trifle dilated at the columellar inser- 

 tion. 



Alt. 2.5, diam. 4 mm. 



Tokunoshima, Osumi. Types No. 87,553, A. N. S, P., from No. 

 1,286 of Mr. Hirase's collection. 



This species differs from M. semisericatus by the more glossy upper 



