117 



Subgen. Segmentina Flem. Testa nitidissima, fau- 

 cibus in omni aetate bis lamellis ternis coarctatis; 

 lamina 1 parietales , 2 laterales, rima intermedia 

 triradiata. 



24. Planorbis nitidus Müll. (Verm. Hist. II, 1774. 

 p. 163.) 



Testa rufa, supra convexa, medio non impressa, spira 

 sat lata, depressa, subtus plano-concava , umbilicata; anfr. 

 4, celeriter accrescentes, ultimus amplior, supra convexus, 

 extus sat praeruptus, deorsum obtuse angulatus, subtus 

 planus, a margine umbilicum versus declivus; sutura non 

 marginata; apertura perobliqua, deflexa, late cordata, mar- 

 gine exteriore forte arcuato. Diam. 5 — 6 mm. 



Planorbis lineatus Jeffreys Brit. Conch. I. 1862. p. 79. 



Hab} tat in fere tota Europa. Terminus borealis in 

 Suecia ad 59 — 60 J , in Fennia ad 62°. 



25. Planorbis clessini Westerl. (Fauna Mollusc. Suec. Taf. 2. Fig. 

 Norv. & Daniae 1873. p. 613.) 2 7 - 30 - 



Testa fulva, supra convexiuscula, medio impressa, spira 

 minima; subtus plano-convexa, anguste umbilicata; anfr. 

 4 — 5, celermnä accrescentes, ultimus forte ampliatus, paul- 

 lulum infra nedium acute marginatus, supra sensim extus 

 depressus, subtus convexiusculus, ab umbilico marginem 

 versus declivus; sutura eburneo-marginata; apertura sub- 

 horizontalis . elongate cordata, margine exteriore extense 

 arcuato. Piam. 6 mm. 



Habiat in Suecia (ins. Oeland, prov. Blekinge et 

 Skane), Eania (ins. Bornholm), Silesia (ad Breslau), Belgia; 

 e Banatu misit. clar. Parreys sub nomine PI. Rossmaessleri. 



(Fortsetzung folgt.) 



