1891.] LAND-SHELLS FROM BORNEO. 37 



Size : maj. diam. 7-6, mia. 7*5; alt. axis 4*6 raillim. 

 Hab. Busan Hills {A. Everett). 



Microcystis (?) macdougalli. 



NaninaC!) tnacdou(/alli, Issel, Ann. Mus. Civ. Geneva, vi. p. 400, 

 t. V. figs. 9-12 (1874). 



Microcystis dyakana, n. sp. (Plate IV. figs. 4, 4 a-4 c.) 



Shell globose, thin, semi-transparent, very narrowly jjerforate, 

 almost imperforate ; sculpture, under high lens very minute, some- 

 what Wiivy sjDiral striation, to the naked eye smooth and glassy ; 

 colour pale dull ochraceous ; spire moderately high ; apex blunt ; 

 suture adpressed, shallow ; whorls 4, convex, rather rapidly in- 

 creasing ; aperture semi-ovate ; peristome sharply edged, reflected 

 at the columellar margin, which is oblique, not thickened. 



Size : maj. diam. 8"7, min. 7v ; alt. axis 4'5 millim. 



Hab. Busan Hills (A. Everett). 



This might very easily be mistaken for Microcystis tersa but for 

 its larger size and fewer whorls, the form of the apex of the shell 

 when viewed from the front being also very different. 



The animal is of a pale ruddy brown colour with large black 

 patches and spottings. 



The right shell-lobe {r.s.l.) very ample, triangular in form ; the 

 left shell-lobe also large as well as the neck-lobes (figs. 4 « & 4 b). 



The radula was not seen, this part had been destroyed before it 

 was placed in spirit. 



The generative organs were also uot perfect. The male organ is 

 shown in Plate IV. fig. 4 c. 



o* 



Microcystis (?) lowi. 



Hyalina (?) lowi, Issel, Ann. Mus. Civ. Genova, vi. p. 401, t. v. 

 figs. 16-19 (1874). 



Microcystis (?) perlucida. 



Hyalina perlucida, Issel, Ann, Mus. Civ. Genova, vi. p. 402, t. v. 

 figs. 20-23 (1874). 



Microcystis (?) miliacea. 



Microcystis (?) miliacea, v. Martens, Preuss. Exped. Ost-Asien, 

 Landschneck. p. 268, plate xii. fig. 1.5. 



Liocystis, Nevill, Hand-hst, MS. (from Amboyna). 



Borneo (Sowerby, ex coll. Lombe Taylor, in coll. Indian Mus., 

 Calcutta). 



There is a doubt both as regards identification and habitats. 



Microcystina infans. (Plate IV. fig. 2.) 



Helix infans, Pfeiff. P. Z. S. 1854, p. 290; id. Monogr. Helic. 

 iv. p. 51 (1859), et v. p. 108 (1868) ; Reeve, Conch. Icon. pi. cci. 

 fig. 1417(1854). 



