Acta Societalis pro Fauna et Flora Fennica, XIII, n:o 7. P'J 



oo 



pressa, tandem lente longeqiie descendens; peristoma conti- 

 nuum affixum; operculum (ut apertura) ovatum, superne 

 angulatum. 



Typus: t. ventroso-conoidea, sat tenuis, nitida, flavido-cornea, 

 anfr. 5—6, superi 3—4 regulariter in spiram brevem 

 late conicam attenuati, ultimi duo majores, plus quam 

 2/3 altitudinis totius occupantes, ult. ventroso-convexas, 

 apert. subovalis, margine colum. fortius incurvato, oper- 

 culum lineis concentricis tantum 1—2 elevatis, Cccteris 

 tenuissirnis; alt. 8—10, lat. 5—6 mm. — Nerita jaculator 

 Miill. (1774), Palud. impura Drap. (1805). 



Forma gigas Morch (Syu. Moll. Dan., 1864}. t. rimata, 

 late ovata, anfr. ult. lineis transversis 2—3 eleva- 

 tis, apice eroso et lamina plana suppleto; alt. 15, 

 lat. 9, ap. a. 7, I. 5 mm. — Suecia in Skane (Hojea). 

 — • Dania in Viborg So, — Fennia in Aland (in 

 l^alude ad Godby: Mus. Helsingf.). 

 Forma intricata W. (Nachr. blatt Mai. Ges. 1894), t. 

 minor, operculum lineis incrementi concentricis 

 omnibus valde elevatis, interstitiis densissime 

 striatulis. — Suecia ad Borgholm frequens. 

 Forma gemina W. (Nachr. blatt Mai. Ges. 1894), t. 

 operculo extus spatio lato l^evi vel striatulo, lineis 

 incrementi concentricis 3—5 internis forte elevatis. 

 — Suec. ad Ultuna prope Upsala frequens. 

 Var. produda Mke. (Sjni. ed. 2, 1830): t. major, elongato-co- 

 nica, solidior, cornea, anfr. 6—7, spira elongata quam apert. 

 longior, acuta, anfr. ult. elongatus, parum convexus, apert. 

 angustior, acutior; a. 12—15, lat. 7—8 (18:10) mm. — Sue- 

 cia in Skane et Ostergotland inventa. 

 Var. ventricosa Mke, (Syn. ed. 2, 1830): t. vix rimata, ventrosa, 

 tenuis at firma, cornea, nitidula, anfi\ 5, sat celeriter ac- 

 cresceutes, convexi, nunc perdistincte, nunc obsolete su- 

 perne ad suturam sat impressam planati et angulati, ult. 

 ventrosus, superi 3 sat abrupte in spiram brevem anguste 

 conicam attenuati, apert. quam spira paullo brevior, rotun- 

 dato-ovata, marginibus seque arcuatis; alt. 10, lat. 7 mm. 

 — Suecia ad Stockholm (Nya Brunnsviken: J. W.). — Fen- 

 nia in Ladoga (Mus. Helsingf). „B. inflata Hansen, telle 

 que je I'ai compris dans ma monographic, avec Bourguig- 

 nat' (Locard in lit.). 

 Var. hottnica (Anders.) CI. (Malak. Bliltt. 1878): t. firma, flavo- 

 virescens vel fulva, forte spiraliter lineata, rugis iucre- 



