L927] Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo 363 
Galateia duponti DAUTZENBERG, 1891, Bull. Ac. Sci. Belgique, (3) XX, (1890), 
p. 577, Pl. 111, figs. land 2. H. pe Corr, 1899, Ann. Soc. Malacol. Belgique, XXXIV, 
Bull. Séances, p. xxxix. 
Galatea dupontt Dautzenberg. C. R. Barremr, 1913, Ann. Soc. Zool. Malacol. 
Belgique, XLVII, (1912), p. 114. | 
Galatea rubrotincta Preston, 1909, Ann. Mag. Nat. Hist., (8) IV, p. 90, Pl. 
Iv, fig. 9. 3 
The type locality of Potamophila radiata J. Sowerby was ‘‘Congo 
River’’ and Sowerby states that his specimens were brought back by the 
survivors of Captain Tuckey’s expedition. Galatea congica O. Boettger 
was described from a left valve drifted up at Banana (P. Hesse Coll.). 
Galateia tuckeyz Dautzenberg was based upon dead shells found in heaps 
along the shore of the Congo estuary between the island of Melella at 
35 kilometers from the sea (probably the same as Malela) and an islet 
opposite the village of Samboela near the confluence of the river Passi- 
konde (= Pasokonde), at 67 kilometers from the sea (this is just above 
Zambi) (EK. Dupont Coll.). Drifted valves referred to G. tuckeyz2 were 
also collected by P. Hesse and at Banana by A. Taquin. Galateca duponts 
Dautzenberg was described from specimens obtained by E. Dupont 
‘dans une poche située dans |’alluvion ancienne du Congo & une quin- 
zaine de métres au dessus des hautes eaux du fleuve, au fond du port de 
Banana, prés de la mission de Nemlao.” H. de Cort noted that A. Taquin 
found near Banana dead specimens, but still fresh and covered with a 
periostracum, of G. duponti, and that Putzeys had seen young, live 
specimens of the same form. C.R. Beettger also reports live G. duponts 
sent by P. Hesse from the Lower Congo. The type locality of Galatea 
rubrotincta Preston is merely given as Congo Delta. ‘“ Kampenzey 
Island,’ where Tuckey first observed the species, is probably what is_ 
now called Mateba. 
We have seen more than a thousand examples from Malela; and a 
few specimens from near Katala, below Zambi (Lang and Chapin, and J. 
Bequaert Coll.). 
The shell is large, very solid, ncaa with very prominent, some- 
what slender beaks. The posterior ridge is strongly developed. It is 
white under a strong epidermis, varying from yellow toward the posterior 
end to olive-brown in the middle and anteriorly. In the most strongly 
characterized individuals there are on the median and anterior part 
about six low, rounded raised rays with concave, concentrically wrinkled 
intervals, extending over about half the valve or less, the earlier part 
being smooth; the posterior ridge has irregular, coarse lumps or con- 
centric waves, also wanting in the earlier stages. In other specimens 
