74 CAUCASIAN LAURIiE. 



f Finely striate. L. fuscidula, no. 52 



1 Closely rib-striate. L. rugulosa, no. 53 



Species of the Caucasus and Transcaucasia. 



The simpler species, such, as L. tenuimarginata, closely re- 

 semble those of Western Europe and the less evolved forms 

 of the Atlantic Islands ; but in most of the species there is a 

 tendency towards further development of the teeth and lip. 

 This culminates in forms having a thick, crenulated lip re- 

 calling the Caucasian Clausilioid genus Serrulina. In others, 

 such as L. caucasica, the columellar lamella is specialized. 

 The species form three series : 



Series of L. caucasica (section Caucasica C. & M.), species 

 no. 15, 16. 



Series of L. tenuimarginata, no. 17. 

 Series of L. superstructa, no. 18-21. 



The following account is in large part given in the words 

 of the able investigators Boettger, Retowski and Lindholm. 

 The figures are chiefly from specimens received from the 

 Boettger collection. I have not been able to obtain L. pau- 

 UncB, L. pontica, and some of the races of other species. 



15. Lauria CxUjcasica ('Parr.', Pfr.). PL 5, figs. 15, 16, 17. 



Shell rimate, oblong-ovate, rather solid, smoothish, glossy, 

 brownish corneous. Spire terminating in a rather obtuse 

 cone; suture subcrenulate. Whorls 8y 2 , rather flat, the last 

 about one-third of the length, compressed at base. Aperture 

 vertical, truncate-oval, contracted by 2 tooth-like parietal 

 lamellae, one subangular, flexuous, entering, the other deep 

 within. Peristome whitish, a little expanded, 5-toothed: two 

 short teeth and an entering fold on the right margin, one 

 basal denticle, and one strong, oblique, deeply entering colu- 

 mellar lamella. Length 6, diam. 3 mm. (Pfr.). 



Caucasus: Mt. Kasbek (Parreyss) ; Kobi, southeast of Kas- 

 bek, central Caucasus (Bttg.). 



Pupa caucasica Parreyss, Pfeifper, Malak. Bl., iv, 1857, p. 

 88 ; Monogr., iv, 675. 



