470 PROCEEDINGS OF THE ACADEMY OF [July, 



Mikuriya, prov. Suruga (Y. Hirase). Types No. 79,724 Coll. 

 A. K S. P., No. 563 of Mr. Hirase' s collection. 



This species i& one of the most extraordinary modifications of the 

 Euphsedusan stock yet known. The large aperture resembles in 

 form that of no other Clausilia known to me, and shows but one 

 lamella, the inferior; the superior lamella being wholly atrophied, 

 and the spiral lamella and principal plica reduced to short laminae 

 in the region where the clausilium lodges. There is no trace of a 

 lunella. The clausilium remains well developed, is slightly thick- 

 ened distally, and has all the characters of that of Euphcedusa. 



In the strong development of the inferior lamella, C. euholostoma 

 resembles C. Hungerfordiana Mlldff. and C. monelasmus Pils., 

 which are likewise deficient in the superior lamella. C. euholo- 

 stoma agrees with the typical forms of Reinia in having the aper- 

 ture wide above, not piriform as in the group of C. Hunger- 

 fordiana. It is intermediate between the two groups in number 

 of whorls and in general contour. 



Section EEINIA Kobelt. 



Reinia Kob., Jahrb. d. D. Malak. Ges., Ill, 1876, p. 34, proposed as a 

 section of Balea ; type Balea variegata A. Ad. 



The type of Reinia is a small tapering -pupoid species, with 

 discontinuous peristome, the aperture being Buliminoid, deficient in 

 lamellae and without plicae, lunella or clausilium. It was included 

 by Bottger next to Balea ; but that group as usually constituted 

 consists of no less than three series of species, each totally dis- 

 tinct and unrelated. 



It was Dr. O. von Mollendorff who with keen insight first 

 pointed out the fundamental distinction between Balea and 

 Reinia. 3 He recognized in the Chinese C. eastlalceana a less 

 modified form of Reinia, and after discussing the characters of the 

 group, declared it to be related to the eastern Asiatic group 

 Phcedusa. The relation of Reinia to Phcedusa, von Mollendorff 

 further held, is comparable to that of Alopia to the true Clausilia 

 of Europe: " Phylogenetisch diirfte Reinia als der lebende Eest 

 der Vorfahren der heutigen Phcedusa- Arcen aufzufassen sein, wie 



3 Jahrb. d. D. Malak. Ges., X, p. 262-265, 1833, under description of C. 

 eastlakeana, a species from Fu-dshow, on the island Nan-tai, province of 

 Fu-dshien, southern China. 



