BURTOA. 301 



Region of the Rek and Djur, tributaries of the Bahr-el- 

 Gasal, in the woods (G. Schweinfurth, March, 1869). 



Achatina nilotica Pfr., v. MARTENS, Malak. BL, 1870, p. 32. 

 Limicolaria n., PFR., Novit. Conch., iv, p. 5, in part, pi. 110, 

 f. 1, 3. Burtoa nilotica BGT., Moll. Afr. Equat., p. 80. 

 Burtoa pethericki BGT., Moll. Afr. Equal, p. 95. Limico- 

 laria nilotica var. schweinfurthi MARTS., Beschalte Weich- 

 thiere, p. 95 (1898). 



There can be no reasonable doubt that the figure named 

 Burtoa petkericki by Bourguignat represents merely the 

 young of the form called schweinfurthi. It is copied on 

 pi. 35, fig. 20. Both specimens are in the Berlin Museum, and 

 were collected by Schweinfurth, not by Petherick, who col- 

 lected the original nilotica. The name B. pethericki has prior- 

 ity for this variety, if a name based upon a figure of the 

 young stage should be allowed to stand, which I doubt. 



Var. schweinfurthi is the form which Bourguignat con- 

 sidered to be the typical nilotica, and the type of the genus 

 Burtoa. 



Var. REYMONDI (Bourguignat). 



' ' This Burtoa, which has been found frequently in the 

 region between the lakes Tanganyika and Nyassa, and Ban- 

 guelo, differs from kraussi Pfr. (the only species having any 

 resemblance to it in appearance and shape) by its smaller 

 size, coloration, shorter, more obtuse spire, more ample last 

 whorl, the wholly covered perforation, straightly descending 

 columella without a projection at its base," etc. 



Bulimus reymondi"BGT., Notice prodromique sur les Mol- 

 lusques terrestres et fluviatiles recueillis par M. Victor 

 Giraud dans la region meridionale du lac Tanganyika, p. 13 

 (1885). Burtoa reymondi BGT., Moll. Afr. Equat., p. 92, 

 pi. 4, f. 1. 



Var. EMINI v. Martens. PI. 29, fig. 7. 



Shell thin, ovate, moderately narrowed above, the aperture 

 about four-sevenths the length. Outer lip about equally 

 arcuate above and below. Columellar lip hardly arcuate, 



