380 



CONCHOLOUY. 



unconnected plate, attached to each valve by an Internal carti- 

 lage, in an oblique descending groove. 



* Myatella itriata, pi. 19, f. 7. Sub-paralli'logrammical , trans, 

 verse, anterior, and truncated ; one erect, broad, doubly.chan- 

 nelled tooth in the left vnlve; none in the other. 



*Crenella elliptic/], pl.19, f.8. Oblong-ovate, equilateral, ven- 

 tricose ; beaks obtuse ; no teeth ; but a flattened crenated 

 plate in each valve. 



*Spenia Rinehami, pi. 19, f- 9. InequiTalve, transverse, ob- 

 long-ovate ; slightly tortuous ; toothless ; cardinal margin flat- 

 teued. 



FAMILY II. SOLKNIDES. 



Glycimeri* Siliqua, pi. 19, f. 10. Equivalve, transverse, (jap- 

 ing widely at each side ; hinge callous, without teeth ; liga- 

 ment external. 



Panopea Aldrovandi, pi. 19, f. 11. Equivalve, transverse, 

 Rides gaping ; each valve with one primary conical tooth, and 

 a callosity on one side ; ligament external. 



Soten Vagina, pi. 19, f. li- Equivalve, much elongated, trans. 

 Tersely ; gaping widely at both sides ; primary teeth, small, 

 bent, and varying in number ; ligament external. 

 FAMILY III. PHOLADARIA. 



Gastrochcena modiotina, pi. 19, f. 13. Equivalve, nearly 

 wedge-shaped ; anterior opening large ; hinge marginal ; 

 linear, no teeth. 



Phola* dactylut, pi. 19, f. 14. Equivalve, transverse ; both 

 sides gaping; hinge with accessory plates; inferior margins 

 inflated. 



FAMILY IV TUBICOLA. 



Teredo navalis, pi. 19, f. 15. Tubular tortuous ; open at 

 both extremities ; a bivalve shell placed posteriorly outside the 

 tube ; f. 16 side valve ; 17 one of the bivalves ; 18 section of 

 Interior part of the tube. 



Teredina personata, pi. 19, f. 19. Tubular, cylindrical, poste- 

 rior extremity closed, but exhibiting the two valves of the 

 shell ; anterior end open. 



Septaria arenaria, pi. 19, f. 20. Tubular, lengthened ; taper- 

 ing anteriorly, divided by imperfect partitions ; anterior end 

 with two slender tubes. 



Fittulana clava, pi. 19, f. 21. Tubular, tumid, closed pos- 

 teriorly ; anteriorly attenuated ; summit open with a bivalve, 

 which gapes. Fig. 22 a side valve. 



Clavagellit aperta, pi. 19, f. 23. Tubular, attenuated, open 

 anteriorly ; posteriorly club-shaped ; a valve attached to one 

 side of its walls, the other within the sheath, unattached. Fig. 

 24 a face valve. 



Arpergillum Jaranum, pi. 19, f. 25. Tubular, attenuating to- 

 wards the anterior end ; posterior end with a club-shaped, 

 spiral termination. 



CLASS III. CIRRIPEDA. 



Animals soft, destitute of head or eyes, covered with an ad- 

 hering shell. 



ORDER I. PEDUNCULATA. 



Body supported on a tubular peduncle. 



Otion Cuvieri, pi. 19, f. 26. Two small semilunar valves, at- 

 tached near the lateral opening. 



Cineras vittata, pi. 19, f. 27. Compressed, five oblong, sepa- 

 rate valves ; two on the sides, the others dorsal. 



Pollicipes mitella, pi. 19, f. 28. Compressed, with many conti- 

 guous valves, lower ones smallest. 



*ScalpeUumvulgare, pi. 19, f. 29. Compressed, valves numer- 

 ous, mostly with a central knob on each, and concentrically 

 utriated. 



Anatifa vitrea, pi. 19, f. 30. Compressed, five-valved, the 

 lower lateral ones largest, adhering by a membrane. 



ORDER II. SESSILIA. 



Body inclosed in a multivalve shell which is seated on rocks 

 or marine bodies ; mouth and tentacula in the opening of the 

 shell; operculated. 



Pyrgoma crenata, pi. 19, f. 31. Seated, univalve, ventri- 

 cose ; opening at the apex, small, elliptical, lid bivalve. 



Creuiia verruca,p\. 19, f. 32. Seated, orbicular, convexo-coni- 

 cal ; valves four, closely united ; operculum bivalve. 



Acasta Montasui, pL 19, f. 33. Seated, ovate, subconic, com- 

 pressed ; six-valved; operculum four. valved. 



*Adna Anglica,pl. 19, f. 34. Seated, cup-shaped, shell of one 

 part, aperture lozenge, operculum four-valved ; f . 35 the lid. 



Salantu Cranchii, pi. 19, f. 36. Seated, four-valved with a tes- 

 taceous plate closing the base; aperture subtigonal; lid four- 

 valved. 



Coronula tettudinaria, pi. 19, f. 37. Suborbicular, valves 

 indivisible, conoid at the extremities; internally hollowed in 

 radiating cells ; aperture roundish, funnel-shaped ; operculum 

 of four obtuse valves. 



Tubicinilla baltenarum, pi. 19, f. 38. Tubular, straight, 

 slightly narrowed towards the base; transversely ribbed; lid 

 four. valved. 



DIVISION III. ARTICULATA. 



CLASS V. ANNELIDES. 



Elongated, soft, consisting of segments ; having red blood. 



ORDER I. SEDENTARE*!. 



Animals placed in a testaceous tube, in which they ever live ; 

 branchiae a,t one extremity of the body. 



FAMILY I. SERPULACEA. 



Magihu antiguiii, pi. 19 f. 39. Base spirally bent, oval, four 

 contiguous volutions prolonged into an erect tube, which is 



convex above, and curinated beneath, somewhat depressed, and 

 plicated on the sides. 



Galeolaria recumbent, pi. 19, f. 40 Tubes numerous cylin- 

 drical, fixed by their base, open at their summit* ; nperture 

 circular, with a spatulous tongue at its termination ; opercu- 

 lum orbicular, with five to nine plates. 



Vermilia triguetra, pi. 19, f. 41. Tubular, cylindrical, pos- 

 teriorly, narrowed, somewhat twisted, adhering to marine 

 bodies by the sides ; aperture circular ; margin frequently with 

 from one to three teeth. 



Serpula tubnlariu, pi. 19, f. 42. Tubular, irregularly contort- 

 ed, grouped or solitary, adhering ; aperture circular and ter- 

 minal. 



Spirorbii spirillum, pi. 19, f. 43. Tube spirally twisted into 

 an orbicular shape, depressed, and adhering beneath. 

 FAMILY II. AMPHITRIT^A. 



Amphitrite ventilabrum, pi. 19, f. 44. Tube cylindrical, taper- 

 ing towards the base, membranous or coreaceous. 



Terebella conchilega. pi. 19, f. 45. Tube cylindrical, elongat. 

 ed, attenuated, and pointed at the base, membraneous, consist- 

 ing of agglutinated grains of sand, or testaceous fragments. 



Sabellaria crassixsima, pi. 19, f. 46. With numerous tubes, 

 united in a common mass, of shelly or sandy fragments ; orifices 

 cup-shaped. 



Pectinarin Belgica, pi. 19, f. 47. Tube in the form of a re- 

 versed cone ; consisting of agglutinated grains of sand. 

 FAMILY III. MALDANI^. 



Dentalium entalis, pi. 19, f. 48. Tubular, tapering, regular, 

 slightly creiiated ; open at both extremities. 



Broc/iut reticulattu, pi. 19, f. 49. Cylindrical, tapering slight- 

 ly, sub. crenated ; imperforate at the smaller end; aperture 

 placed at the larger end ; orbicular. 



Cornuoidet minor, pi. 19, f. 50. Cylindrical, tapering, the 

 smaller end spiral and closed, broad end with a circular aper. 

 ture. 



Clymene. Tube slender, open at both extremities, and in- 

 crusted externally with grains of sand and fragments of shells. 

 FAMILY IV. DORSAI.I.-K. 



Si/iquaria anguina, pi. 19, f. 51. Tubular, irregularly twist- 

 ed, posteriorly tapering, sometimes spirally ; open at the ante, 

 rior extremity, with a longitudinal cleft, extending along it* 

 whole length. 



Arnicola. Destitute of shell. 



EXPLANATION OF THE PARTS OF 

 SHELLS. 



OF THE OPERCULA OF UNIVALVE SHELLS. 



The opening, or aperture of many univalve shells, is cover- 

 ed, when the animal is withdrawn within, by an operculum or 

 lid, intended for the protection of the inhabitant. This is at- 

 tached to the foot of the animal, and is either of a horny sub- 

 stance, or is testaceous, being as hard as the shell itself. This 

 appendage will be familiar to all who have seen the common 

 periwinkle which is abundant on most rocky shores. Its tex 

 ture is of a horny nature. 



Operculum of Nerita Undulata, pi. 19, fig 52. Phasianella 

 Bullmoides, 53. Trochus Pharaonis, 54. Melania Byronensis, 

 65. Neritia fluviatilis, 56. Panludina achatina, 57. Turbo 

 Pica, 58. Neritoides littnralis, 59. Murex Brandarig, 60. 

 Buccinum undatum, 61. Strombus Amis-Diana, 62. Trochus 

 littoralis, 63. 



Animal of the Monodonta Pica f. 64, a, tl>e tentacula or feel- 

 ers; 6, the trunk ; cc, the pedicles, with the eyes at their tips ; 

 dd, the branchiae or gills ; et, mantle ; /, foot ; g, the opercu- 

 lum ; h, the tail, or that extremity of the animal which occu- 

 pies the volutions at the tip of the shell. 



The following are the shells figured, explanatory of the dif 

 ferent parts : Fig. 65, Fusus antiquus ; 66, Voluta vesperti- 

 lio ; 67, A lusus naturae of Helix Pomatia ; 68, Spirula Pero- 

 nii ; 69, Cassis ariola; 70, Cypraea exanthema; 71, Clausilia 

 ventricosa; 72, Planorbis Plauata ; 73, Crepidula aculeata; 74, 

 Fusus discrepans ; 75, Dolium galea ; 76, Turitella terebra ; 

 76,* Helix Umbilicata; 77, Cytherea Chioue; 78 Hinge of 

 Lutraria elliptica ; 79, Solen truncatus ; 80, Cardium elonga- 

 tum; 81, Spondylus gaederopus; 82, Anomia squamula; 83, 

 Cardium edule ; 84, Venus Cassina ; 85, Pecten obsoletus ; 86, 

 Pholas candidus; 87, Anatifa striata ; 88, Balanus communis; 

 89, Operculum of Balanus Cranchii ; 90, Chiton cinereus. 



Apex, is the summit or tip of the spire, pi. 19, f. 65 a. 



Base, the opposite extremity to the apex, pi. 19, f. 656. In 

 simple univalves, such as the patellae, it is the margin of the 

 aperture, the tip of the vertex being the apex. Example of 

 the base in a depressed shell, pi. 19, f. 72 b. 



Body. The lower volution of the shell in which the aperture 

 is placed, pi. 19, f. 65 m, m, m. 



Front, is the place where the aperture is situated. 



Back, the opposite of the front, opposed to that in which the 

 aperture is situated. 



Venter, the most bulging part of the front, pi. 19, f. 65 c. 



Sides, the extreme edges of the shell, pi. 19, f. 65 dd. Right 

 is the opposite to that in which the aperture is situated. 



Aperture, the mouth or opening #. 



Beak, the elongated process at the base of many genera of 

 univalves, pi. 19, f. 65. ', f. 75 c. 



Canal, the inside of the beak, pi. 19, f. 63. h, 75 A. 



Pillar or columella, is that process which runs through the 

 spire, for the support of the volutions, f. 76 a. 



Platted columella, is when there are folds at the base of the 

 pillar lip, f. 66 a. 



Pillar lip, a continuation of the enamelled process which 



