400 Bulletin American Museum of Natural History [Vol. LIII 
Zaira Simpson, 1900, Proc. U. 8. Nat. Mus., XXII. p. 862. Mlisspelling of 
Zaria. 
Reneus JOUSSEAUME, 1886, Bull. Soc. Zool. France, XI, p. 481. Type by tau- 
tonomy: Reneus reneus Jousseaume. 
Renatus A. T. DE RocHEBRUNE, 1904, Bull. Mus. Hist. Nat. Paris, p. 257, foot- 
note. Emendation of Reneus. 
Celatura section Horusia Patuary, 1924, Mém. Inst. d’Egypte, VII, 1, p. 43. 
Type by original designation: Unio rugifer Kister. 
? Celatura section Nitia Pauuary, 1924, Mém. Inst. d’Egypte, VII, 1, p. 43. 
Type by original designation: Unio teretiusculus Philippi. This group is probably 
valid as a subgenus, whether referable to Czlatura or Parreysia remains to be seen. 
Celatura section Iaronia Patuary, 1924, Mém. Inst. d’Egypte, VII, 1, p. 44. 
Type by original designation: Unio niloticus Cailliaud. 
“Shell elliptical, pointed or rounded behind, usually slightly produced at the 
post-base; beak sculpture consisting of zigzag ridges which are generally quite pustul- 
ous, the sculpture often extending on to the usually rayed disk; teeth compressed; 
pseudocardinals lamellar.”” (Simpson, 1914, ‘Descript. Cat. of Naiades,’ p. 1019.) 
Simpson says (op. cit., p. 951) that he examined the soft parts of C. 
equatoria (Morelet): there seemed to be no striking differences in the 
more obvious characters from the majority of the Uniones, but the 
embryos filled the inner gills above as in Diplodon. 
While many species can be referred to this group from their simi- 
larity with C. zgyptiaca in beak-sculpture, form, and teeth, yet there 
remain some forms which could as well be placed in “‘ Parreysia.’’ The 
relations of Unio and Parreysia to Czlatura remain to be worked out. 
Subgenus C&LATuRA, proper 
Celatura elegans (A. T. de Rochebrune) 
Plate XX XII, Figures 5 and 6; Plate XX XIII, Figure 4 
Zairia elegans A. 'T. DE ROCHEBRUNE, 1886, Bull. Soc. Malacol. France, III, p. 
12. Simpson, 1900, Proc. U. 8S. Nat. Mus., XXII, p. 862. 
Nodularia (Cexlatura) elegans A. T. de Rochebrune. Simpson, 1914, ‘ Descript. 
Cat. of Naiades,’ p. 1032. 
Unio (Nodularia) roubaudi GERMAIN, 1907, Bull. Mus. Hist. Nat. Paris, p. 429, 
fig. 28 (new name for Zairia elegans de Rochebrune). 
Gancini or Nganchu, on the right bank of the Congo River (type locality; Thollon 
Coll.). Bamu Island in Stanley Pool (Roubaud Coll.). 
Zambi (Lang and Chapin, and J. Bequaert Coll.). ‘Leopoldville 
(J. Bequaert Coll.). Malela (Lang and Chapin Coll.). | 
The rather plump, thin, oblong or elliptical shell is dull citrine-drab, 
varying toward green or gray in different individuals. It varies from 
slightly to decidedly higher behind than at the beaks, which are between 
the anterior fourth and fifth of the ghell’s length. There is a rather 
large lunule bounded by angular ridges. The beaks have posterior and 
