MOLLUSQUES TERRESTRES ET FLUVIATILES. 
291 
SECTIO XV. 
GEOTROCHUS, Hasselt. 
51. Hélix trigonostoma, Pfeiffer. 
Helix trigonostoma, PfeifFer, dans Philippi, Abhildimgen , I, vir, p. i54, pl. IV, fig. 8, i8ù4. 
Helix trigonostoma, Pfeiffer, Proceed. Zool. Soc. of London, part XIII, p. hi. i845. 
Helix trigonostoma , Chemnitz, ed. nova, p. 992, ])i. KLIX, fig. 10, i848. 
Helix trigonostoma, Pfeiffer, Monog. Heliceonm, vol. I, p. 229, i848. 
Helix trigonostoma, Reeve, Conchol. Iconica, ]>1. CV, fig. 584, 1862. 
Geotrochus trigonostomiis , Pfeiffer, Vers. p. i45, i855. 
Geotrochus trigonostomus , Albers, 7/e/<cm«, e'd. Martens, p. 812, 1860. 
Testa imperforata, conica, trochiformis , tenuiascula, suhoblique striatiila , lineisnonnuUisconcentricis,imjnms- 
sis notata, alba, fasciis suj)erne linearibus, basi latioribus , fusco-violaceis ornata; spira late conica; sutura 
impressa; anfractus h ijü planiusculi, primi 1 sublcevigati, niiululi, ultimus leviter descendens, spiram 
superans, obsolete angulatus, basi subjdanatus ; apertura subtriangularis , lunato-ovalis , parum obliqua, intus 
albida , fasciis anfractus ultimi transmeantibus ; peristoma simplex, rcfexum, lacteum, margine columellari 
brevi, extus calloso, appresso, basali et externo expansis , supero ad insertionem attenuato. 
Diam. maj. 37 mill., min. 32, ait. 18. 
Var. ( 3 , luteo-albida (pl. Xf, fig. 6), paulo minor; anfractus â 3 jù, fasciis linearibus ü , fusco-nigricanti- 
bus transversim cincti , punctis nigricantibus, raris, parum conspicuis, obscure notati, ultimus fasciis à ornatus, 
tertia basali, lata, quarta latiore, locum umbilici circumdante; aqyertura vix subtriangularis , lunato-ovalis , 
alba , fasciis transmeantibus. 
Diam. maj. ^5 mill., min. 20, ait. 16 (Mus. Parisiense). 
Far. y, elevato-conica (pl. XI, fig. 6 a), alba; anfractus 5 , fusco-nigricante quadrifasciati , jmnctis raris- 
simis, obscuris inconspticue notati , ultimus basi late bifasciatus ; apertura lunato-ovalis, alba , fasciis transmean- 
tibus. 
Diam. maj. 27 j/2 mill.,7nin. 22, ait. 20 (Mus. Parisiense). 
Var. S, intermedia (pl. XI, fig. 6 4 ), striatula, pallide cinereo-lutescens , fasciis linearibus ( ultima majore ) , 
sat numerosis , fusco-nigricantibus cincta , et qmnctis plurimis irregulariter asqyersa; anfractus 5 , ultimus imjmes- 
siombus obsoletis vix rugulosus, infra pervpheriam albidus, basi fusco sat late bifasciatus, cinereo-lutescens , 
juxta aperturam vitta castanea longitudinaliter ornatus; apertura subanguste lunato-ovalis, alba , fasciis et 
vitta transmeantibus. 
Diam. maj. 37 mill., min. 22, ait. 18 (Mus. Parisiense). 
Animal lutescens, lateribus griseo longitudinaliter bifasciatis; tentacidis griseis. 
Var. e, Scdleana, paulo major, conica, tenuiuscula, striatula et impressionibus obsoletis rugidosa, parum 
nitida, cinereo-lutescens, ad peripheriam fasciis 2 fusco-viridibus et punctis castaneis ornata; anfractus 5 vix 
convexiusculi , idtimus lineis impressis, concentricis notatus, subangulatus , basi parum convexus; apertura 
parum obliqua, lunato-ovalis, intus nitida, albida, fasciis nigricantibus; peristoma tenue, expansum et 
refexiusculum , album, margine columellari superne dilatato, calloso. 
Diam. maj. 3 o mill., min. sâ, ait. 2 4 . 
