86 



CONCHOLOGY. 



Univalve?. 



Lacustris, 



Cariaatu- 

 las, 



!\>fhtU3, 



xxi i r. 



Orthoce- 



BA. 



Recta, 



iUdicuIa, 



Subarcua- 

 ta, 



Jugosa, 



Gostata, 



Tfejumen, 



of the interior volution ; mouth oblique, scarcely clasp- 

 ing the body. 



Test. Min. Rar. tab. 3. fig. 70. 

 ' Test. Brit. tab. 18. fig. 2. 

 On the English coast, rare. 



11. Lacustris. Shell compressed, subcarinated, spi- 

 ral, smooth, glossy; horn-coloured ; above convex ; apex 

 depressed with three visible volutions ; these are bor- 

 dered on their outer edge with an opake whitish line ; 

 under side flat with a deep cavity ; chambers distant ; 

 mouth narrow, subcordate, clasping the body whorl ; 

 diameter nearly a quarter of an inch. 



Phil. Trans, vol. xvi. tab. fig. 1 — 7. 

 Test. Min. Rar. tab. 1. fig. 28. 

 Test. Brit., tab. 6. fig. 3. 

 In marshes and ditches in England not uncommon. 



12. Carinatulus. Shell oblong, carinated, with a nar- 

 row oval aperture; colour whitish, transparent like 

 glass. 



Test. Min. Rar. tab. 3. fig. 72. 

 From Seasalter and Sandwich, very rare ; Mr Wal- 

 ker. 



1 3. Inflatus. Shell opake, brown, with three lobated 

 whorls ; in the first whorl are five extremely ventricose 

 articulations ; anterior end sub-globose ; syphon placed 

 as in N. beccarii. 



Test. Brit. tab. 18. fig. 3. 

 Found amongst sand on the coast of Devon by Mr 

 Montagu. 



Genus XXIII. Orthocera. 



Shell straight, or slightly bent, rather conical, the cham- 

 bers separated by transverse septa, which are pierced by a 

 tube. 



1. Recta. Shell straight, or a little arcuated, with 

 smooth joints; smaller at the posterior extremity than 

 at the mouth. 



Test. Min. Rar. tab. 3, fig. 74. 

 Test. Brit. tab. 19, fig. 4 and 7. Nautilus. 

 Found at Sandwich by Mr Boys ; very rare. 



2. Radicula. Shell sub-conic, elongated, with eight 

 or nine sub-globose articulations; smooth, opake, brown; 

 aperture a small syphon. 



Test. Brit. tab. 6. fig. 4-, and tab. 14, Fig. 6. Nautilus. 

 This species varies much in shape. Found at Sand- 

 wich by Mr Boys. 



3. Subarcuata. Shell sub-cylindric, sub-arcuated, with 

 three conspicuous globose articulations at the larger end, 

 the remaining joints being scarcely visible; mouth a 

 email produced syphon ; colour pellucid, glossy, white ; 

 length a tenth of an inch. 



Test. Brit. tab. 6. fig. 5. Nautilus. 

 Found at Sandwich by Mr Boys. 



4. Jugosa. Shell sub-arcuated, sub-cylindric, a little 

 tapering, with nine ridged globose articulations ; mouth 

 extended to a small conical syphon ; the extreme joint 

 at the smaller end longer than the others near it ; length 

 about the eighth of an inch. 



Test. Brit. tab. 14, fig. 4. Nautilus. 

 Found by Mr Boys on the Kentish coast. 



5. Costata. Shell straight, sub-cylindric, a little ta- 

 pering, with twelve raised articulations, furnished with 

 four equidistant, strong longitudinal ribs running the 

 whole length of the shell ; mouth extended in a coni- 

 cal syphon ; length a quarter of an inch. 



Test. Brit. tab. 14, fig. 5. Nautilus. 

 Found on the Kentish coast by Mr Boys. 



6. Legumen. Shell sub-arcuated, smooth, glossy, com- 



pressed, and nearly of equal size throughout ; the ends Uufvalw* 

 are rounded, and a little contracted ; the anterior end """ "V"*"'' 

 surrounded with an oblique margin above, which rises 

 into an obtuse syphon; chambers eight or nine in num- 

 ber, with oblique septa ; length an eighth of an inch. 

 Test. Min. Rar. tab. 3, fig. 74. 

 Test. Brit. tab. 19, fig. 6. 



Found in sand on the coast of Kent and South De- 

 von, by Mr Montagu. 



7- Spinulosa. Shell with three extremely globose s„i nu i osa 

 articulations of a pale chesnut colour, covered with 

 spines; the superior bulb a little elongated, to form the 

 syphon; the spires all incline to the posterior end; 

 length one-tenth of an inch. 



Test. Brit. tab. 19, fig. 5. Nautilus. 



Found by Mr Boys. 



8. Bicarinala. Shell sub-cylindric, arcuated, with Bicarinata, 

 eleven sub-globose bi-caiinated articulations ; the joints 

 gradually decrease a little to the posterior end, which 



is rounded ; length one eighth of an inch. 

 Test. Brit. Sup. page 86. Nautilus. 

 Found by Mr Boys at Sandwich. It resembles in 

 shape the O. subarcuata. 



9. Linearis. Shell straight, linear, a little compres- 

 sed, and nearly of equal size throughout ; furnished 

 with faint ribs at the lesser end, which take an oblique 

 direction, and scarcely extend half the length of the 

 shell ; chambers about fourteen in number ; anterior 

 end smooth, with a produced syphon, posterior end 

 rounded ; length a quarter of an inch. 



Test. Brit. tab. SO, fig. 9. Nautilus. 

 Discovered by Mr Montagu amongst a parcel of mi- 

 nute shells sent to him from Dunbar by Mr Laskey. 



Linearis. 



Genus XXIV. Spirolina. 



XXIV. 



Shell in part spirally convoluted ; the turns contiguous; Spirolina. 

 the last whorl produced, and straight at the end -/cham- 

 bers divided by transverse perforated septa. 



1. Semilitua. Shell elongated, sub-arcuated, with Semilitua, 

 elevated joints ; apex incurvated ; mouth with a small 

 produced syphon ; colour opake, brown. 



Test. Brit. tab. 19, fig. 3. Nautilus. 

 On the English coast. 



2. Subarcuatnla. Shell sub-arcuated ; anterior part Subarcua- 

 of the shell with about four chambers, posterior half tula ' 

 convoluted ; back carinated, and slightly indented at 



the division of the cells ; front margin obtusely round- 

 ed ; length one-eighth of an inch. 



Test. Brit. tab. 19, fig. 1. 



Test. Min Rar. tab. 3, fig. 73. Nautilus. 

 From Shippy island, very rare, Mr Walker. 



Genus XXV. Miliola. 



XXV. Mi- 



Shell transverse, ovate-globose or elongated, with trans- " otl ' 

 verse chambers involving the axis, and in three directions ; 

 the opening small at the base of the last chamber. 



6bs. The species which we have included in this 

 genus, belong to the genus Vercniculum of Mr Monta- 

 gu. He separated them from the genus Serpula of Lin- 

 naeus, from the circumstance of their being indepen- 

 dent, or not attached to other bodies. Their multilo- 

 cular cavity point out their connection with the shells 

 we have been just now treating of, so that we have wil- 

 lingly adopted the genus which Lamarck formed for 

 their reception. 



1. Bicornis. Shell white, opake, with three cham- Bicomis, 

 bers, the middle one small, the outer ones rounded and 



