moe: Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo : AAQ 
Many supposed species have been defined, but in the latest con- 
siderations of the genus by von Martens (1897), by Germain (1907), 
and by Anthony (1907) all are recognized as forms of one species. E. 
tubifera and E. cailliaud: will probably be considered a distinguishable — 
subspecies, the former mainly West African, the latter mainly Nilotic 
and East African. Ro . 
According to Simroth and Germain the spinose forms grow in quiet, 
the smooth in rapid water. In some places smooth and spinose indi- 
viduals appear to occur together, or at least are associated in lots having 
one field label. A careful study of an Htherza colony is needed. Anthony 
(1907, Ann. Soe. Zool. Malacol. Belgique, XLI, (1906), Pl. xu, figs. 18 
and 19] figures an interesting specimen fixed upon a valve of Aspatharia 
WISsmannt. 
The soft parts and anatomy of Ktheria were briefly studied by Rang 
9 
and Cailliaud! and more recently with much detail by Anthony? and 
Sassi.3 | 
Etheria elliptica Lamarck 
Plate XLVI, Figures 1, la; Plate XXX, Figures 2, 2a 
Etheria elliptica Lamarck, 1807, Ann. Mus. Hist. Nat. Paris, X, p. 401, Pl. 
xx1x and Pl. xxx1, fig. 1 (the exact type locality is not mentioned. Lamarck wrote: 
‘on la dit originaire de la mer des Indes’’). SowxErsy, 1872, ‘Conchol. Iconica,’ 
XVIII, Htheria, Pl. 1, figs. la-b. 
Zitheria elliptica Lamarck. E. v. Marrens, 1897, ‘Deutsch Ost Afr., IV, Be- 
schalte Weichth.,’ p. 216 (with form globosa, p. 218). Van DEN Brascxk, 1898, Ann. 
Soc. Malacol. Belgique, XX XIII, Bull. Séances, p. li. HE. A. Smrrn, 1904, Proc. 
Malacol. Soc. London, VI, 2, p. 103. Grrmain, 1905, Bull. Mus. Hist. Nat. Paris, 
p. 261; 1908, in A. Chevalier, ‘L’ Afrique Centrale Frangaise,’ p. 547; 1908, ‘Rés. 
Scientif. Voy. Afrique Foa,’ p. 678; 1909, Bull. Mus. Hist. Nat. Paris, p. 276, Pls. 
ui and tv; 1911, op. cit., p. 441. J. Taree, 1911, ‘Wiss. Ergebn. D. Z. Atr. Exp. 
(1907-08),’ III, p. 218. W. Wettner, 1913, op. cit., IV, pp. 477 and 481. Dautzen- 
BERG AND GERMAIN, 1914, Rev. Zool. Afric., IV, 1, p. 67. Spencn, 1922, Journ. of 
Conchology, XVI, p. 266. 
Aitheria elliptica var. typica “ Germain” AnrHony, 1907, Ann. Soc. Zool. Malacol. 
Belgique, XLI, (1906), p. 372 (new name for the typical, smooth form of E. elliptica). 
Etheria trigonula Lamarck, 1807, Ann. Mus. Hist. Nat. Paris, XK; p40 Pl. 
xxx and Pl. xxx1, fig. 2 (also originally said to be from the “mer des Indes”; accord- 
ing to Bourguignat, 1880-1881, ‘Matér. Moll. Acéph. Syst. Europ.,’ I, p. 66, a Ms. 
note of Lamarck stated that it was from Senegal). 
1Rang, P., and Cailliaud, F. 1834. ‘Mémoire sur le genre Ethérie et description de son animal,’ 
Nouv. Ann. Mus. Paris, (3) III, pp. 128-144, 1 PI. 
2Anthony, R. 1905. ‘Influence de la fixation pleurothétique sur la morphologie des Mollusques 
acéphales dimyaires.’ Ann. Sc. Nat. Zool., (9) I, pp. 165-400; Pls. VII-Ix. (Etheriide, pp. 339-372) . 
1907. ‘Etude monographique des Aitheriide (Anatomie, morphogénie, systématique).’ Ann. Soc. 
Zool. Malacol. Belgique, XLI, (1906), pp. 322-430, Pls. x1-xII. : 
38assi, M. 1910. (Beitrage zur Kenntnis der Anatomie von Aitheria tubifera Sow. Zool.) Anzeiger, 
XXXVI, pp. 25-31. 
