1927] Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo 419 
In specimens which have only a small area eroded at the beaks, a 
well developed corrugation is seen anteriorly and posteriorly, or posteriorly 
only. The middle region, next to the eroded area, shows under the lens 
a fine concentric costulation, the costule irregular in greater or less 
degree. At a rather early neanic stage, this species has therefore much 
the Aspatharia sculpture. | 
The specimens from Aba, where it appears to be somewhat abundant, 
are all smaller than those from Medie. 
An apparently constant character of this species is that, as in A. 
rubens and some others, the right valve is higher than the left in the 
region of the small but distinct lunule. 
Other Species of Aspatharia, proper, Recorded from the Belgian Congo 
Aspatharia semicorrugata (Preston) 
Spatha semicorrugata Preston, 1909, Ann. Mag. Nat. Hist., (8) VI, p. 90, Pl. rv, 
fig. 7. Smmpson, 1914, ‘Descript. Cat. of Naiades,’ p. 1349. 
Lower Congo (type locality; no collector mentioned). 
Aspatharia stuhlmanni (EK. v. Martens) 
Spatha stuhlmanni BE. v. Martens, 1897, ‘Deutsch Ost Afr., IV, Beschalte 
Weichth.,’ p. 260, fig. Simpson, 1900, Proc. U. 8S. Nat. Mus., XXII, p. 900; 1914, 
‘Descript. Cat. of Naiades,’ p. 1338 (locality incorrectly given as “Lake Albert 
Nyanza’’). 
Undussuma (type locality; Stuhlmann Coll.), in the region of the Ituri River; 
probably from the river itself and its affluents, for instance in the Duki River near 
Buessa in 1° 30’ N.; the detached valves are used as spoons by the Babira natives. 
This appears to be closely related to A. sinuata(v. Martens). 
Subgenus SpatHopsis Simpson 
Lamellidens subgenus Spathopsis Stmpson, 1900, Proc. U.S. Nat. Mus., XXII, 
p. 857. Monotype: Anodonta guillaini Récluz. 
Spatha subgenus Spathella Bourcuienat, December, 1885,‘ Esp. Nouv. Ouk. 
Tanganika,’ p. 14. Type by designation of Bourguignat (1889, ‘Moll. Afrique 
Equator.,’ p. 195, footnote): Spatha petersi KE. v. Martens. 
Leptospatha A. T. pba RocHEBRUNE AND GERMAIN, 1904, Mém. Soc. Zool. France, 
XVII, p. 25. Substitute for Spathella Bourguignat (December, 1885), not of J. Hall 
(November, 1885). Type by designation of Germain (1909, Arch. Zool. Expér. 
‘Gén., XLI, p 49, footnote): Spatha petersi E. v. Martens. 
Mitriodon A. T. pE RocHEBRUNE, 1904, Bull. Mus. Hist. Nat. Paris, p. 462. Type 
‘by present designation: Mitrio on martini A. T. de Rochebrune. 
Spatha of authors, not of I. Lea, 1838. 
The following species belong in this group: 
Aspatharia (Spathopsis) adansoni (J ousseaume) =Spatha adansont JOUSSEAUME, 
1886, Bull. Soc. Zool. France, XI, p. 498, Pl. x1v, figs. 4-4a. Simpson, 1914, ‘ Descript. 
‘Cat. of Naiades,’ p. 1325. Diamuko River, near its confluence with the Senegal. 
