from Portuguese Saiith-east Africa. 117 



lustre to the shell ; suture simple, deep. Aperture rouuded- 

 liiii;ito : peristouie tliiii, siui[)Ic ; columcli.'i short, upper 

 iii;ir;;iu imrrowly reHexed, but not coucealiug the very 

 narrow, tliouj^h deep, uuibilicus. 



Diain. uiaj. 3U, uiin. 35; alt. 3-2; apert., ait. 2-1, hit. 

 r? nun. 



I i/jit'-lucaliti/. District 10 miles north of Macc([uece, 

 4500 ft. {B. dressy). 



Note. — The sculpture of the seven minute species which 

 follow is dcdcrihcd subject to a majjnihcatiou of about 50. 



Trachycystis mcdoivelli, sp. n. 



Shell very small, depressed, circular, umbilicate, thin, 

 silky, translucent, corneous. Spire almost flat. Whorls 4\, 

 rounded, slowly and regularly increasing ; protoconch faintly 

 microscopically punctate, showing traces of transverse stria- 

 tion after the first whorl ; remaining whorls covered with 

 very close, clear, nearly straight, transverse, raicrosco[)ic 

 striie ; suture uai'row, but well-defined. Aperture lunate ; 

 peristome simple, acute ; umbilicus rather narrow, extending 

 to the summit and just exposing all the whorls. 



Diani. maj. l'?, miu. 1'5 ; alt. circa 08 mm. 



Type-locality. Maforga Siding, B. & M. Railway ( B. F. 

 McDouell). 



Trachycystis rudicostata, sp. n. 



Shell minute, umbilicate, nearly flat, thin, transparent, 

 j)ale corneous. Spire but little raised, ai)ex submamillate. 

 Wliorla 3i, convex, rather rapidly increasing, the apical 1^ 

 microscopically punctate and clearly, closely, spirally striate ; 

 remainder sculptured on both sides with prominent, raised, 

 curved, oblique, transverse lira>, increasing in distance toward 

 the aperture and becoming laraelliform on the periphery ; 

 between each of these are very close transverse, crossed by 

 equally close spiral, striae ; suture simple, deep. Aperture 

 nearly circular ; peristome simple, columelhir margin not 

 reriexed, umbilicus wide and deep, extending to the summit 

 and exposing all the wliorls. 



Diam. maj. 18, min. 16 ; alt. circa 00 mm. 



Type-locality. Dargic, Natal (//. C. Burmip) : also found 

 on Mt. Veil go, Maceciuece {/J. Crvssy). 



