.4 



llHiiMALACUS MACULDSrS. 



ill cnlnur, MiiiieUines willi iiniisl iiirlly iiiilir.ateil ilarker siiliiUirsal ami latcrHl liaiiils, 

 wliicli usiiall\' extend tlie hIidIo leii;;lii iif tlie liody, aixl arc iliie to the liody 

 l)ciii!;' ii\ers|ii'ead liy iiniiiemii.s smnewlial. owil yidlowisli spots, «liicli are, liowever 

 clistrilmted more or less ]peiee|itiiily in lue loii,i;itudinal zones; SIIIKIJ) aliout one- 

 tliiid (lie length of tlie liody wliou crawl in;;', but only alxiut lialf size when the 

 animal is contracted, rounded in front and liluiitly jiointed Ijehiiid, sliafjreened and 

 spotted with soinewhat similar but more uuifornily distributed pale butt or whitish 

 spots than those on the body ; KOOT-FiaNilK not very distinctly separated, \-ery pale 

 ami soinewhat expanded, with indistinct lineolatiou ; SOLE pale diisky-ocli'reous, 

 indistinctly trifasciate, with the mid-area somewhat darlcer and more transparent 

 than the sides; i.'AUt)Ar, cijAN'li triangular, not very conspicuous, opening trans- 

 versely between the foot and the boily, and often carrying a transparent yellowish 

 ball of slime; UPl'Ei; TKXTAt^LES smoky-black or grey, short and thick,' but with 

 (n-al extremities, ami bearing the usual eye-specks at their summits ; I.OWEK 

 TEX'iACLES pale Iraiisluccnt grey. 



DEUJIAE-Aircns usually pale-yellow and variable in its degree of viscosity. 

 L(jCoM(i-i'oi;v-Mri'i-s tenacious and usually colourless, but nniy lie stained by the 

 intermixture of the dermal slime. 



SiiKLL resembling that of Linui.c, of an oval 

 shape, solid and calcareous, with a transparent 

 coiichiolin base, usually somewhat convex above 

 and concave beneath, with a few indistinct con- 

 centric lines of growth, and, according to Godwin- 

 Austen, coi'ered outwardly with a very thin trans- 

 |)arent ejiidermis and with the boss or nucleus near 

 the front. In young animals, the shell is very thin 

 and convex, abru]itly cut oft' liehind, bnt with a 

 [irojectiiig granular lilin in front. 



(ntei;x'.\llv, the ALiMEX'iWKV CAN.VE resembles 

 that of Aridii ; the IIEAKT is completely snrj-ouuded 

 liy the triangular renal or.gaii or KIDNEV, which is 

 of lamellate structure, and discharges by means of 

 a piimary and secondary UKK'tKR; in ihe iireseiit 

 grou]i the ventricle of the heart is directed towards 

 and in close |iioximity to the ANAL and respjila- 

 Toliv oujFiCES, Avliile in Arinn it is more remote 

 and ill a more posterior position ; the st'l'itA- 

 I'EiiAL (;l.\ni> is deeply imbedded in the tissues 

 and reaches far back; sE;\ri'Et;"s , iiitiLVX is well 

 developed and chielly shown as a [lair of strong 

 tlatteneil lobes; the S.VLIV.VR'i' and iiiclstive 

 fiLANDS are as in Arioii, but the vestigial osph- 

 radinni within the mantle chamber is more distinct. 



The CEl'llALir RETILVCTfiKS have the tyjiical 

 Aiionine clmiacter ; the right and left TEXTAcui^.V!! 

 muscles di\ide early for Ihe upper and lower 

 tentacles, but only thosi' of the oniniatophore are 

 darkly pigmented, and are attached basally to the 

 right ami left posterior mantle margins' respec- 

 tively; the ril.VliVNilEAL retiiudm- is, as usual, 

 furcate for altachnicnt to the n-a.r of lln' I'.LCCAL 

 liirLI), its rool being lived on the right-side id' the 

 body, just liehind the point of livali'on of the right 

 tentacular iiiiiscle. 



The iiErii(ii>ijiAn\-E oMiAXs possess a small, 

 coni|iart, ami darkly iiigmented (i\(n'Esris, and the 

 ]iEi!MAi'iiii(iii|-n.; [iiM-r is \eiy long and greatly 

 coiuoliilcd, tciniinaliiig in a small spherical \t:sL 

 CLLA SEMIN.M.IS ; the ,\ 1 ,11 1 1 M I '.N CLVNII is elmu;- 



ati-d and liiiLoiifoini ; i>\isrr;i:M \ romri < r j^i^,, vi>'ry i 

 lilJL't rather long and tliiii, but wdthout any eiiiarj 

 long, complexly twisted, and rolled up in the form' 

 ghdinlar, with short st(nn, bu|. i|uit'e distant from tl 



x^V 



Fig. 2.59.--Shell 



of C. 1l1acilhs}<s 

 X 6. 



(Lou^h Car.-igh, 

 Co. Kerry, t\.. K. 

 .Scharff). 



I 

 ^\ Fic. 260.— 



\ liraiii-riiig of G 



if riiaciihsvs, froi: 



/ beneath, en!ar<^e( 



(after .Scharff). 



Fic;. 2lil.-fal]ial organs and 

 oe|)halic retractors of ii. ji/at'nhh^as 

 X ;i (after CJodwin-Austen). 



Ii. lieart ; /.-. kidney ; /./. left 

 tentacular retractor ; r.f. ri;:;ht 

 tent.acillar retractor ; ;■, rectum ; 

 /.w, pliarynv;ea] retractor. 



inch t«isted ; the KliFE OVl- 

 ;ement; \'AS iii;KEt!FNS very 

 of a bundle ; si'FKMVniFf'A 

 (> genilal apeiliiri^ owing to 



