CAUCASIAN LAURLE. 79 



18a. L. superstructa lederi (Bttg.). PI. 9, fig. 5. 



Appearance of the shell and conformation of the peristome 

 as in caucasica Pfr., but armature of the aperture that of 

 superstructa Mouss. Shell larger than the type, more cylin- 

 dric, paler, corneous-olivaceous; aperture not so wide, the 

 right margin more impressed, the peristome simple, not 

 doubled, whitish, not orange. No folds or denticles in the 

 palatal margin except for a median, long palatal fold and a 

 single punctiform denticle on the right margin and one in the 

 base of the aperture. Length 5*4, diam. 2% mm. {Bttg.). 



Nakerale Mts., Imeretia, Hans Leder, one specimen. 



Dr. Boettger further remarks in substance that this form 

 differs from superstructa chiefly by the simple, thickened 

 whitish lip, not doubled and not orange-colored. In dentition 

 it differs by having the right parietal lamella arise from a 

 wholly simple base, and its duplex nature only revealed by a 

 scarcely noticeable little knot on the right side ; the pointed 

 tubercle on the right margin limiting the sinulus is not con- 

 tinued inward as a fold. Besides this tubercle, and with the 

 exception of the long basal-lamella [lower-palatal fold] and 

 the basal tubercle between this and the columellar lamella, no 

 traces of any denticles are to be seen either within the mouth 

 or on the thickening of the right margin. Figure reproduced 

 from Boettger. 



18&. L. superstructa unibasalis (Bttg.). PI. 9, figs. 6, 7. 



Differs from the type, of Kutais, by the non-tuberculiferous 

 larger parietal [angular] lamella; a single palatal fold, there 

 being no small upper one and none between the palatal fold 

 and columellar lamella. Length 5, diam. 2% mm. (Bttg.). 



Suanetia. Fig. 6 after Boettger, fig. 7 a topotype from the 

 Boettger collection. The absence of upper-palatal and basal 

 folds readily distinguish this subspecies. Length 4.6, diam. 

 2.35 mm., 7% whorls. 



19. Lauria zonata (Boettger). PI. 9, figs. 8, 9, 10. 



Much smaller than the type (of superstructa), uniform 

 corneous-brown or generally paler, corneous-olivaceous with a 



