112 



rotunda, parura obliqua; peristoma albo-labiatura, subtiliter 

 nigrolimbatum , lamella tenui continuum. Diam 5 — 6 mm. 

 Habitat in Germania et Bohemia. 



Taf. 4. Fig. 15. Planorbis devians Porro. (Malacol. terr. fluv. della 



13 ^5 ' 



prov. di Comasca, 1838. p. 84.) 



Testa solida, subcrassa, pallide Cornea vel albida, 

 transversim saepe ruguloso-striata , lineis spiralibus incon- 

 spicuis, supra convexa, subtus concava aut latissime et pro- 

 funde umbilicata; anfr. 4^, celeriter accrescentes, sub- 

 rotundi, ultimus maximus, latus, depressus, medio angulatus, 

 subcarinatus, utrinque aeque plano-convexiusculus, ad aper- 

 turam deflexus (ad inferum devians: Porro); apertura per- 

 obliqua, magna, ovali-rotundata; peristoma simplex, con- 

 tinuum, affixum. Diam. 7 mm. 



Planorbis deformis Hartmann Erd- und Süssw.-Gaster. 

 1844. p. 95. 



Planorbis cavatus Westerlund Exp. Grit. Moll. 1871. 

 p. 133. 



Habitat in Bodensee. 



Variat interdum haec species testa majore, utrinque 

 aequaliter plana, medio vix depressiuscula, anfr. 5'/ 2 , lentius 

 accrescentibus, ultimo antice paullulum deflexo. 



Taf. 2. Fig. 16. Planorbis borealis LovSn. 



23—25. _ . . 



lesta supra convexmscula, in centro depressa, Cornea, 



subtus sat profunde concavo-umbilicata, subtiliter transver- 

 sim striata, minutissime et dense spiraliter lineata, vix niti- 

 dula; anfr. 5, celeriter accrescentes, omnes teretes vel ulti- 

 mus depresso-teres, antice obtusissime et obsoletissime angu- 

 latus, utrinque aeque convexus, ad aperturam plus quam 

 duplo latior, non dilatatus, nee deflexus, anfr. penultimus 

 altus, cylindraceus, supra ultimum undique multo elevatus, 

 anfr. primi depressi; apertura obliqua, non deflexa, longe 

 tarnen non horizontalis, margine superiore anfractus ultimi 

 paullulum declivi, margine columellari aperturae quam 

 anfr. penult. multo profuudior curvatus; peristoma late 



