4G8 ^li-. n. B, Preston on 



Trachijcystts pJannlata, sp. n. (Fig. 13.) 



Shell depressedly suborbicular, with nearly planulate spire, 

 perforate, tliin, horny, pale olivaceous ; whorls 4^, rather 

 rapidly increasing, the last descending in front, angled at the 

 periphery, marked with coarse, oblique, somewhat arcuate, 

 transverse riblets; suture well impressed; base of shell 

 slightly convex ; umbilicus moderately wide, deep ; colu- 

 mella descending in a very oblique curve; labrum thin, 

 narrowly reflexed ; aperture broadly sublunate. 



Alt. 5*25j diam. maj. 11, diam. min. 9 mm. 



Aperture : alt. 5, diam. 5'5 mm. 



Uab. Mount Kenia, at an altitude of 9000-10,000 feet, 

 British East Africa. 



Trachycystis pseudocharopa, sp. n. (Fig. 14.) 



Shell small, suborbicular, depressed, almost planulate, 

 somewhat thin, light brown ; whorls 3^, sculptured with 

 rather coarse, closely set, oblique, arcuate costulse; suture 

 impressed; umbilicus moderately wide, deep; columella 

 vertically descending; labrum simple, acute; aperture 

 broadly sublunate. 



Alt. 1'25, diam. rn.-ij. 2*5 mm. 



Hab. Naivasha, British East Africa. 



A |)retty little species, forcibly reminding one of some of 

 the New Zealand and i^.us'ralian Churopidie. 



TracJiycfjStis appro.vimans, sp. n. (Fig. 1,5.) 



Very closely allied to T. pseiidocharo2)a, but diflering in its 

 much finer sculpture and less depressed form, the prrseiit 

 species being depressedly turbinate. 



Alt. 1*5, diam. maj. 2'5, diam, min. 2 mm. 



A]ierture : alt. "5, diam. about ".') mm. 



Hah. Between Ru nruti and Mou it Konia, British East 

 Africa. 



Trachycystis rvgosa, sp. n. (Fig. 16.) 



Shell small, de|iresse(lly orbicular, covered with a pale 

 brown periostracum ; whorls 3|, regularly increasing, sculp- 

 tured with distant, rather coarse, transverse costulae, between 

 which occur fine, closely-set, transverse striae ; suture deeply 

 impressed ; base of shell slightly inflated ; umbilicus wide, 

 deep ; columella obliquely descending, a callus joining it 

 with the lip above ; labrum simple ; aperture subcircular. 



