BOYSIDIA. 203 



5, the upper marginal and strong, the rest weak, immersed, 

 visible from the outside by their opacity. Color pale tawny, 

 the peristome white. Alt. 3, greatest diam. 2 mm. ; aperture 

 1% mm. high and wide (B. & D.). 



French Indo-China: Ban-Lao; Muong-Hum and Muong- 

 Kong (Messager). 



Boysidia lamothci BAVAY ET DAUTZENBERG, Journ. de Con- 

 chyl., 1912, p. 21, pi. 3, f. 7-9. 



' ' This species is especially remarkable for its globular shape 

 and the complication of the folds of the aperture. ' ' 



The palatal plicae vary in number and size. Sometimes (fig. 

 3) there are only the two usual plicae, but in others (fig. 5) 

 there are in addition two in the basal position and an inter- 

 palatal, or five in all; the lower palatal plica being scarcely 

 larger than those on each side of it. There may also be some 

 minute folds below the columellar lamella. In fig. 5 the upper 

 palatal plica is nearly concealed behind the nodule of the lip- 

 callous. In an obliquely basal view (fig. 4) the very strong 

 and long angular lamella is seen to stand entirely free of the 

 parietal. The infraparietal is very deeply immersed. Under 

 a strong lens the smaller plicae and columellar lamella are seen 

 to be minutely spiniferous. The surface is most minutely 

 granulous. The specimens figured are from Ban-Lao, the 

 type locality. 



8. BOYSIDIA PAVIEI Bav. et Dautz. PL 35, figs. 7, 8. 



Shell small, thin but opaque, turbinate, rather widely um- 

 bilicate. Spire pyramidal, the apex rather obtuse. Five con- 

 vex whorls joined by a conspicuous suture, ornamented by 

 very fine, scarcely visible growth-lines. Last whorl not 

 ascending in front. Aperture subtriangular, rather oblique. 

 Peristome continuous, a little dilated. Two strong parietal 

 lamellee, nearly equal, but the superior is a trifle stronger and 

 marginal, the inferior being a little immersed. Columellar 

 lamella strong, subhorizontal. Four palatal plicae, the upper 

 marginal, the rest immersed, and all visible through the outer 

 wall. Color brown, the peristome and teeth paler. Alt. 1%, 

 greatest diam. 1% mm. ; aperture % mm. high, % wide. 

 (B. & D.) 



