1927] Pilsbry-Bequaert, The Aquatic Mollusks of the Belgian Congo 197 
having the base chamois. There are sometimes brown streaks, though 
these are less conspicuous than in Kobelt’s figure. In one of the ex- 
amples from Zambi (Pl. XVII, fig. 5) the color is almost black. The 
surface is very glossy, without microscopic sculpture. 
Length, 38.0 mm.; diameter, 31.0 mm. 
Phy Ske Sead ioe eee 
This is probably what was recorded from the Congo (v. Mechow 
Coll.) as L. ovum by E. v. Martens, 1882, Jahrb. Deutsch. Malakoz. 
Ges., IX, p. 248. | 
Lanistes (Meladomus) procerus (E. v. Martens) 
Lanistes olivaceus var. procerus EH. v. Martens, 1866, in Pfeiffer, ‘Novit. Con- 
chol.,’ II, p. 292, Pl. txx1, figs. 1 and 2 (described from an unknown locality); 1897, 
‘Deutsch Ost Afr., IV, Beschalte Weichth.,’ p. 164. 
— Celadomus olivaceus var. procerus E. v. Martens. Kopertt, 1911, in Martini 
and Chemnitz, ‘Syst. Conch. Cab., n. F., I, Ampullartide,’ p. 6, Pl. xx11, figs. 1 and 2. 
. Dupuis and Putzeys (1901, Ann. Soc. Malacol. Belgique, XX XVI, Bull. Séances, 
p. lviii, fig. 29) refer to procerus specimens from Nsendwe (Dupuis Coll.). It is ex- 
tremely probable that these examples belonged to the race described below as L. 
procerus langt. 
Lanistes (Meladomus) procerus langi, new subspecies 
Plate XVII, Figures 1-4 
Stanleyville (type locality), common in quiet brooks near the Congo 
River; often covered with alge; about 170 adult specimens (Lang and 
Chapin Coll.). Luapula River at Kachiobwe (Stappers Coll.). Lake 
Kisale at Kikondja (J. Bequaert Coll.). 
The specimen from Kikondja was recorded by Dautzenberg and 
Germain (1914, Rev. Zool. Afric., IV, 1, p. 51) under the name Lanistes 
ovum var. elatior E. v. Martens. 
The shell is narrowly umbilicate, buffy-olive to ecru-olive, glossy, without 
microscopic lines, smooth or malleate, and in old shells having coarse, low wrinkles | 
along lines of growth. The spire varies individually in length, and is always eroded 
above, leaving 3 to 345 perfect whorls. The broadly ovate aperture is bay, darker or 
lighter, within, with a white or pale yellow band bordering the lip and spreading 
inward at the base. The narrow columella is pale yellow to light pinkish cinnamon. 
Length, 65.0 mm.; diameter, 52.0 mm.; aperture, 40.0X29.5 mm. _ 
eae 6: 3.) fe 47.0 35.0X 26.0 Type. 
oo ae i 50.0 i 36.0X28.0 
We have felt much uncertainty about the identification of this form. 
Dupuis submitted specimens from Nsendwe (which appear from his 
remarks to agree with ours from Stanleyville) to von Martens, who pro- 
