MoUusca from Central Africa. 59 



Suhulina viurin(/oensis, s[). n. (L'^ig. 3.) 



Sliell subulate, shining, lliin, yellowish horn-colour ; 

 wliorls 9, somewliiit convex, sculptured with fine transverse 

 stria;, which are more marked iuimediately below the sutures ; 

 sutures deeply impressed, crenellate ; columella arched, 

 curved, obliquely truncate; labrum acute ; aperture inversely 

 auriform. 



Alt. 14, diam. maj. 3'5 mm. 



Aperture: alt. 2'2o, diam. 1*25 mm. 



JJab. Maringo Plateaux, Belgian Congo. 



'J"he species may be compared with S. octona, Linn., but is 

 much less blunt at the apex and has considerably more convex 

 whorls. 



Limmea anceyana, sp. n. (Fig. 4.) 



Shell fusiformly ovate, thin, semitransparent, pale yellowish 

 liorn-colour ; whorls 5, rapidly increasing in size, the last 

 somewhat laterally contracted, marked irregularly with lines 

 ot" growth; sutures well inij)ressed; columella descending 

 obliquely, twisted and ditVustd into a very thin callus whicli 

 reaches the lip above; labrum acute; aperture elongately 

 ovate. 



Alt. 19, diam. maj. 7, diam. min. 5 mm. 



Aperture : alt. 9, diam. 5 mm. 



Hal. Maiingo Kiver, Belgian Congo. 



Unio angoniensi'Sf sp. n. (Fig. 5.) 



Shell ovate, slightly angled posteriorly, covered with a 

 blackish-brown laminiferous periostracum ; sculptured with 

 closely set, irregular, concentric growth-lines, and posteriorly 

 with curved, transverse, interrupted, slightly nodulous riblets; 

 umbones much eroded, rather large, moderately prominent; 

 dorsal margin soinewiiat ascending, scarcely arched ; ventral 

 margin nearly straight; anterior side abruptly rounded; 

 posterior side sloping above, then angled and descending 

 sharply below ; lateral teeth elongate, curved ; cardinal tooth 

 in right valve elongate, erect and jagged anteriorly, partially 

 cleft posteriorly ; cardinal tooth in lel't valve somewhat 

 triangular, broad, tuberculous in the middle, erect and jago-ed 

 at the sides ; anterior adductor scars deeply impressed, ovate ; 

 posterior adductor scars light ; interior oi: shell nacreous, pink 

 anteriorly, livid bluish posteriorly. 



Long. 26, lat. '6d mm. 



llah. Angoniland, British Central Africa, to the south of 

 Lake Nyassa. 



