INTRODUCTIO. XI 



iractala sunt, quarum utraque genera comprehendit nuda et testa 

 praedita. In familia Arionidarum genera sunt sequentia : a. Arion, 

 Phosphorax, b. Helicarion, c. Nanina, Stenopus, d. Zonites — 

 in familia Helicidarum haec: a. Limacellus, Scutelligera (e classe 

 Molluscorum jamdiu eliminata), Mehimatium (Meghimatium van 

 Hass., Fer. ), b. Limax, c. Parmacellus, Cryptella, Pectella, Vitrina. 

 Helicolimax, Omalonyx, d. Plectrophorus, e. Testacellus, f. Helix, 

 Streptaxis, Anostoma, Helicodonta, Polydontes, Pleurodonta, 

 Dentellaria, Carocolla, Iberus, Chilotrema, Odontoslylus, Heli- 

 cophanta, Tapada, Amphibulina, Epistylium, Mesomphyx, Pro- 

 serpina, Delomphalus, Hyalina, g. Bulimus, Megaspira, Pupa, 

 Abida, Clausilia, Balea, Siphonostoma, Bulimulus, Succinea, 

 /i. Achatina, Macrospira, Polyphemus, Achatinella. 



25) J. D. W. Hartmann 1840 (Erd- und SUssw. Gasl. I. 

 Syst. Uebers. ) in Pneumoneatis Geophilis sequenlia habet genera: 

 Auriculam, Clausiliam, Chondrum, Pupam, Bulimum, Helicem 

 (cum subgen. plur.), Helicophantam, Testacellam, Vilrinam, Suc- 

 cineam. 



26) Swainson 1840 (Treat. on Malac. p. 160 et .326.) in 

 familia Helicidarum omnes sectiones Pulmonatorum comprehendit. 

 Dispersa reperiuntur genera Heliceorum in subfamiliis Limacina- 

 rum (Vitrina, Stenopus, Succinea), Lucerninariim (Leiosloma, 

 Lucerna, Lucernella, Pusiodon, Thelidomus), Helicinarum (Holix, 

 Geotrochus, Pupa, Helicella), Achatinarum (Clausilia, Bulimus, 

 Achalina). 



27) Reeve 1841 (Proc. Zool. Soc. p. 76.) et 1842 (Conch. 

 syst. II. p. 64.) familiam Colimaceorum in Pulmobranchiatis habet. 

 Genera: Helix, Carocolla, Anostoma, Pupa, Clausilia, Bulimus, 

 Partula, Achatina . Succinea. 



28) Gould 1841 (Invert. of Massach. p. 169.) eodem nomine 

 Colimaceorum familiam designat, ex qua genera Iractantur: Helix, 

 Pupa, Bulimus. Succinea (et Auricula). 



29) A. Catlow 1845 (Conch. Nom.) omnino systema Reevea- 

 num sequitur, addito genere Achatinella. 



.30)Agassiz 1847 (Nom. zool. Ind. univ.) nomen familiae 

 mutandum proponit in: Helicoidae. 



De omnibus hisce auctorum methodis et de vario modo, quo 

 ipse familiam tractaverim, conferantur in Herrmannsen ind. 

 gen. Malacoz. prim.: Helicea. Helix Cuv., Colimacea otc. 



^. 3. 



Crenera adoptata. 



Etsi in familia Heliceorum typi sufficientes existcre videantur 

 ad formanda et determinanda bona genera , tum ex animalium 

 structura peculiari, tum c testarum figura, tamen dinicillin\uni 



