IIKLI 



HKLK 





rahMsk lUre eaah fan., far iu.lf . wtth U 



i .l.rfa<. < .rity.. . Jy Wry, to co*rta 



.*y h III M I ed eaaavatea by toruinf i 



*j^ i*^r.*i. aewf agate* the aide* of th. 



far ftMlf. wHh the anurior put of lU 



tin l IMA lU .I..-1I : 

 iwlf round on every 

 i cavity, UK! at tut 

 or leaves, oc small quantity of earth 

 Wbro it KM succeeded in briugin? 



. 



of the .ll u, nearly horizontal potion, it u.i TU 

 .Mlmtil within the shell, the nail Own expand*, 



e*ant***tj to cover the oottar of the mutl, which U at thi. period 

 c/.ni ; ao4 UM. bernta* a quantity of air. a/Ur which it cloee. 

 the Minaory Ma Whe thi* i* dooe, a DM transparent membrane 



lyiag above. 



between the ui.ntlr and 



- - . 



boU surface, which eete uui- 

 continuous 

 , the animal 



uooiu aecre- 



fe.1 aad after a f.w boors, expelling a portion of the air it had 

 piUaly inHml. it enabled to ahrtnk a little farther into the 



-k^-JI ! m. mn i til ff }mmtnm itt tdtlill* AwfUMM tnnCW Air mill 



qoaouty of vrry white fluid over iu whole surfac*. whi 

 Wv.'hh* plaster of Paris, and intently forming a 

 eareA.; ahoot half a line thick. When Uu. u hardened, 

 epsjnte* it* mtl* from to by another and stronger mu 



It'oow'form* another lamina of mucus, expire* more air, and 

 UHM retires farther into the shell In this way aometimea a fourth, 

 Ah. a*jd even sixth partition are formed, with intermediate cell* 

 Had with air. 8och u M. Oanard's account, but Mr. Bell remark* 

 thai it doaa not completely explain the manner in which the excava- 

 tton M fawjil ~ It i* not by the pressure of the foot," *ay* the 

 T--1H-H- 1 aooiogMt, -and the taming round of the shell, that thi* i* 

 principally efttUd. A large quantity of very viscid mucu* i* secreted 

 oeitheaader 



i of the fool, to which a layer of earth or dead 

 j thu i* turned on one aide, and a fresh accretion being 

 thrown oat. the layer of earth mixed with mucu* U left. The animal 

 the* take* another layer of earth on the bottom of the foot, turn* it 

 also to the part where he intend* to form the wall of hi* habitation, 

 and leave* it m the earne manner, repeating the proceu until the 

 cavity it romcwotly large, and thu* making the tide* amooth, even, 

 aad compact. In fanning the dome or arch of the form, a cimilar 

 aaethnit U need, the foot collecting on it* under surface a quantity of 

 earth ; and the animal turning it upward*, leare* it by throwing out 

 fivah njucoa, and thi* i* repeated until a perfect roof i* formed. A* 

 watched thi* c 



I hare very often 



thi* curious prooeat, I am certain of the 



Can*. OB removing very carefully a portion of the roof aoon after its 

 , I was enabled to tee the formation of the operculum. In 

 ir, or even leas, after the hybcrnaculum is covered in, the 

 i of the collar of the mantle instantaneously pours out 

 I secretion in considerable quantity. Thi* is at first as 

 fluid a* thick (learn, but very soon acquire* exactly the consistence of 

 bird-lime, being excessively adhesive and tenacious ; and in about an 

 boor after it la poured out it is perfectly solid." 



M. Oa*rird states that the labour of each individual continues for 

 ; but that the whole of the month of October 

 of the shells of the specie*. He 

 in) the hibernation cease*. "The 



mode by which their escape from confinement is effected is simple 

 a*d easily HNIipni bended. The air which is contained in the different 

 0*0*, aad which had been expired on the animal withdrawing itself 

 farther and farther into the shell after the formation of the operculum, 

 Is agate iaepired, aad each sepsrate membranous partition broken by 

 the premvre of the hinder parts of the foot projected through the 

 mantle. When it arrive* at the calcareous operculum. the animal, 

 masTi.gasiMe.fcrt, burst, and detaches it* most obtuse angle. Then 

 inriMirisg by IHUe and little the edge of the foot between the shell 

 and the opereulum, it force* the latter off, or break* it away." 

 C Abstract of M. (Wpard's Memoir,' by T. Bell, Esq., Prea. L. &. 

 Zoological Journal,' vol. i.) 



W oow iironiJ to give a sketch of the view* of lystematuU with 

 nmd to this amemos tribe of fitT^li 



The genus i*tr (Slug,* i* placed by Linnams at the bead, of the 

 JtfeUaws) in his Ust edition of the 'System* Katune,' and is numbered 

 ibersdSJg, a 



Tb g*aus Udu u numbered 398, aad consequently U widely 

 ed by him from Lima*. Both land aad fresh-water testaceous 

 MnB4* tssimllij under this genus, which stead* between 



er"* Puuwnca Trrrestres, or TerrasUial Pnlmonifnrou* Mo|. 

 (ska. inmirtiJ of the Hluga, Limaos* (Umas of Linusus, including 

 ;*"'*. T**tdU, ao.1 ParmacMa), the l-iargots, (//eJir), thi 

 X<mp*U ( aW, Drap,). and the Agatiae* (AdMma Lam!). 



Cndvr ////.^ Cuvier arraagr* UtlU, Ti/naa ( Helicolimnx ), 

 fmlimmt, ft ft. CaesWnu, and Omecimtm. 



, -:" 





U* CoUmaets to be Air-Breathing Trachclipods 

 '-. provided with or deprived of an operculum, 

 MM teteck. Their shell he characterisM 

 -_. projecting parU on it* exterior except tl- 

 *d nbssto (eostoJ.) of gr.,wth, and whoee apnture is often 

 osjtwcrda. He divide, this, the first family of 

 (PU.t-E.ting) TracheUpoda, into the following 



(a) Four TeuUcles. 

 /Wir, CarteoUa, Anotloma, Jlflitina, Pupa, Claitnlia, />/im, 



(t) Two Tentacles. 

 A uricula and Cyclottomo. 



M. de Feruaaac makes thu fourth .ml liftii orders of Gastropoda 

 __oaiat of the rulin.niilVr.m.1 Uiutropod* without an operculnia 

 (Pulmonos aan* Opercule), aud the Puluioniferous Gastropod* with 

 an op<Tculum (Puluionos Upercul<Ss). 



Tlie fourth order consists of the following suborders and genera : 



1st Suborder. Gtopkila. 



The 1st Family of this order consists of the different genera of 

 Slug*, and of I'armaettta, Tatacella, Ac. 



The 2nd Family embraces the following genera of SnaiU : - ////- 

 carion, Hrlicvliwai; J/dir, Vertigo, Parluta. 



2ud Sub-order. GeMydrophila. 



8nl Family (I.e* Auricules), Carychium, Scarabiu, Auricula, Pyra- 

 muUUa, TurnatelUi, Pedipct. 



3rd Sub-order, llygrojihila. 



Thi* sub-order consist* of the LinmenuB, or Water-Snails, such a* 

 I.imnaa, Ptanorbii. Ita. 



The fifth order coutaina two families : 

 lufe The H.-liciniiuiH (//,?i !,.< >. 

 2nd. The Turbiciniang (Cyclustvma). 



The Pulmvliranrliiaia form the first orclur of U. De Blainville's 

 Paraeepkalopltora Monoiea, the second subclass of the second clans 

 (Paretpkalopkora) of his ifalacosoa. 



M. 1> Blainville gives the following description of the Puimo- 

 brancktata : 



Organs of respiration retiform or aorion, lining the roof and fioor 

 (plafond) of the cavity situated obliquely from left to right on the 

 origin of the back of the aiiiiual, and c'unmmiicnting with the ainbii'iit 

 fluid by a small rounded orifice, pierced on the right Bide of the 

 swollen (renfle 1 ) border of the mantle. All these animals are more, or 

 lea* framed for breathing air ; the greater part are terrestrial ; gome 

 live on the banks of fresh waters, and others on the sea-banks (rivage 

 dea men). None bury themselves in the mud, with the exception of 

 the Limnaceang, during the rigorous season ; all are phytiphagous. 

 Some of them are known in all lands. 



M. De Blainville divides the Pulmobranchiata into the following 

 families aud genera : 



1st Family, the Limnaceans. (Limn rn, Phyta, Planorbit). 



'2ml Family, tho Auriculaceons. (Pedipa, A nri,-ul<i, J'i/r<iinitlttla.) 



3rd Family, the Liniacininug. . Jliihnin.i, Acha'ina, 



Clatuilia, Pupa, Tumoyerrt, Jlcti.r, Jicltcolimax : Tatacella, }' 

 crila, Limacdla, Litnax, OncHulium.) 



M. Latreille divides the Pulmonos, his fourth order of his first 

 section of Gastropods (the Hermaphrodite*), into the following 

 families and genera : 



lit Family, Mudiliuiaces. (The Slugs, and ParmaccUa, Titta- 

 ceUa, Ac.) 



Jn'l Family, G^ocochlides. (/fclicarion, Vitrint (Helicolimax), 

 Succitiea, lltltjc, Carocolla, Anottoma, i'li/m, Chundru* (Citx-tiaille), 

 Clatuilia, Bulimia, Ackutina, Yirtiyo, I'tirtula.) 



3rd Family, Limnocochlide*. \Cary--hium, Scaralmi, Auricula, 

 C'uRorn/0, Ciutiiiula, Limnau, I'liyi, J'/<uiorl>it, Ancyliu.) 



The second section, tin' l>i<uciou Gastropods, coni.<tH of hU liftii 

 order (Pne*pomtt), and coutaius two families: 1st, the Hcliuiniilr* 

 ia); 2nd, the Turbiciues (C'ycloitoMa.) 



M. Kwng, in his ' Tableau Mdthodique,' makes the Limacons of 

 F<Sru*sac ^Trachdlipodes Colimaocs of Lamarck ; Limaciuoa of De 

 Blainville; Goocochlides of Latreille) the second l.imily of the 

 Pulmonos luoporcule's of Fdrussac (Pulmobranches of I > l;i.-iinville). 



M. lUng, following De Fonnwac, thus, with some slight alteration*, 

 defines aud arranges the family : Aniiiml elongated, having tlie body 

 distinct from tlie foot, and forming a twisted npiral, rarely furnished 

 with a cuirass, but always showing a fleshy collar which closes the 

 shell. Teutacula to the number of four, rarely two, the upper 

 ooellated. Pulmonary cavity placed forward, and opening in the 

 thickness of the collar. Organs of generation nnit..i in front ; vrnt. 

 near the respiratory orifiee. Shell always spiral, very variable in 

 form, receiving the animal more or lean completely. Terrestrial. 



TETRACBROUS. 

 A. A cuirass and a collar. 



Genera, Vitrina, Draparnaud. (//eliculimaj- an<l // :!inirio of 

 Ferusaac.) 



B. A collar without a cuirass. 



Genera, //efi>, Muller (Hclir, Succi, <, Acarut, 



Pulftlontrf, Towugera, Anottoma, Carocolla, JJtUimu*, Ac/uitina, Poly- 

 fkaiuu, Pupa, C'tttiuUiu, ic., 4c.. FIT.) 



(t) Itcdunit 

 $ Volutata . Udicoida. 



