﻿C L A U S I L I A. 



Plate I. 



Genus CLAUSILIA. Unq-wnaud. 

 Tifta terrestris, ■plerumtpie sinistralis, turrita, fuslfor- 

 mis, apertitrd pliis niinusve auriforwi, )'///».'■■ 

 lamina libera sulqyirali tesfaced clavsd, colxiiwUi'i 

 pleriimque hiplicatu. 

 Shell terrestrial, generally sinistral, tnrretcd, fusiform, 

 aperture more or less anriforin, closed within by 

 a free subspiral shelly plate, columella generally 

 with two plaits. 

 The Clausium, shown at fig. 7. ciiii only lie seen 

 in situ, by breaking the last whorl of the shell. 

 It is of a subspiral form and turns on the edge 

 of the inner part of the columella by means of 

 a cartilaginons hinge. The animal can thereby re- 

 treat further within his shell and shut himself up 

 more securely than by means of the ordinary external 

 operculum of other shells. The species of this in- 

 teresting genus of land shells are found everywhere 

 in Europe, in China, and Chinese and Indian Islands, 

 and generally in temperate districts. AVe have not 

 been able to identify, among our 165 species taken 

 principally from the British Museum and our own 

 collections, half of the species enumerated by Pfeiffer, 

 whose long and laborious studies, almost entirely 

 confined to the air-breathing molluscs, have enabled 

 him to present so complete a list. Our enumerations, 

 however, include the great bulk of tlie species likely 

 to be met with, and most of the more interestLng 

 and striking forms. 



Species 1. (ilus. Sowerby.) 

 Clausilia teidens. Cla. testa pup<vformi, medio suhin- 

 Jtato, fmeo, profunde perpendicitlarilcr sidoato ; 

 anfractibus setiis permanentihus, altis, idtimo 

 elongato, angustato, infra prolonrjato, ■prufii.nde 

 rimato, suhtortuo; aperturd magna, latd,suli'puul- 

 raid, superne elevato, acuminato ; margine alhv, 

 crasso, expa^iso ; plied parietali crassd, plied co- 

 lumellari parvd, elevatd, plied suhcoluinellari in- 

 eoiispicud. 

 The theee-toothed Ci.ausili.\. Shell pupa-shaped, 

 a little inflated below, brown, deeply perpen- 

 dicularly grooved ; whorls six permanent, high, 

 last elongated, narrow, prolonged below, deeply 



notched, a little tortnous; aperture large, broad, 

 rather square, i-aised above, acuminated ; margin 

 white, thick, expanded ; parietal plait thick, 

 columellar plait small, raised, under- columellar 

 jilait inconspicuous. 



CiiKMxm (Turbo). Pffr. Mon. Hcl. II. S'JO. 



Turho costHlatns. Wood. 



Clausilia lahiata. Sowerby. 



JIah. Porto Rieo. 



Species 2. (Mus. Brit.) 



CLADSlLrA Baktletti. Cla. testa subrosed, brevissimd, 

 ventrieosissimd, solidd, Icevi ; anfractibus quinis, 

 iribiis maximis, inflatis, idtimo angustato, pro- 

 longafo; aperturd subanriformi, labio externo 

 supra meditim sinuato ; plied parietali magna, 

 plied columellari suhtrigond. 



Baktlett"s Clausilia. Shell somewhat pink, very 

 short, very ventricose, solid, smootli ; whorls 

 five, three very large, inflated, last narrowed, 

 prolonged ; aperture subauriform, outer lip 

 sinuous above the middle ; parietal plait large, 

 columellar plait subtrigonal. 



A. Adams. Proo. Zool. Soo. 1866. 



Eah. Eastern Peru. 



Species 3. (Mus. Brit.) 



Clausula bii-licata. Cla. testa fusiformi, ventrieosd, 

 pruinosd, temiissimit striatd ; anfractibus novenis, 

 injiatis; aperturd uhluugd; margine albo, labli 

 interno biplicato. 



The two-plaited Clausilia. Shell fusiform, ventri- 

 cose, plum-coloured, very finely striated; 

 whorls nine, inflated ; aperture oblong; margin 

 white, inner lip two-plaited. 



MoxTAor, Brit. Biv. 



Udix perversa. jVIull. 



Clausilia Montagui. Gray. 



Sab. Germany, Spain, Great Britain. 



Species -1. (Fig. a, b, Mus. Sowerby.) 

 Clausilia Eokmosessis. Cla. testd fusiformi, ventri- 

 eosd, sulidd, fulvd, vel pruinosd; aufniclihus un- 



