484 
Explana- Fig. 40. Mur ex tribulns, thorny woodcock, 
tionofth. Fig. 41. Trochus telefcopmm, telefcope-top (hell : a, 
■ ' . the bafe 3 b , pillar projecting, fpiral 3 c, outer lip di- 
lated. 
Fig. 42. Turbo fcalaris , wentle-trap 5 a, a, cancel- 
lated wreaths 3 b , b, membranaceous cingula 3 c, fpire 
acute, papillary 3 d, aperture circular 5 e, e, lip re- 
flexed. 
Fig. 43. Helix lufitanica ; a, umbilicus 3 b, b, b, 
round venter 3 c, clofed, femilunar aperture. 
Fig. 44. Helix decollata. 
Fig. 45. Nerita canrena ; a, umbilicus gibbous, 
Index. 
deep ; b, b , outer lip dilated, arched, entire 3 c, lip of Explana. 
the pillar tranfverfe, truncated. tion of the 
Fig. 46. Haliotis varia ; a , a, ribs acute, and ftri- Fla tes - 
atea crofswife 3 b , lateral fpire, with its margin den- 
tated. 
Fig. 47. Patella faccharina j a, a , feven ridged acute 
ribs 3 b, obtufe vertex. 
Fig. 48. Dentalium arcuatum , arched tooth-lhell. 
Fig. 49. Serpula glomerata. 
Fig. 50. Teredo navalis, (hip-worm. 
Fig. 51. Sabella alveolata. 
CONCHOLOGY. 
INDEX of tlie Genera, Jhewing the page on which the Clarification of each Genus begins. 
A. 
D. 
Anomia, 
P- 4 J 9 
Dentalium, 
p. 461 
Area, 
4 J 3 
Donax, 
408 
Argonauta, 
422 
H. 
B. 
Flaliotis, 
455 
Buccinum, 
402 
Helix, 
448 
Bulla, 
428 
L. 
C. 
Lepas, 
402 
Cardium, 
406 
M. 
Chama, 
412 
MaCtra, 
407 
Chiton, 
401 
Murex, 
43 8 
Conus, 
424 
Mya, 
4°3 
Cypraea, 
425 
Mytilus, 
420 
I N D 
N. 
Solen, p. 404 
Nautilus, 
p. 423 
Spondylus, 412 
Nerita, 
453 
Strombus, 437 
O. 
T. 
Qftrea, 
414 
Tellina, 404 
Teredo, 463 
P. 
Trochus, 442 
Patella, 
456 
Turbo, 445 
Pholas, 
453 
Pinna, 
422 
V. 
S. 
Venus, 408 
Sabella, 
463 
Voluta, 429 
Serpula, 
462 
E X. 
N° 25 
11 
A 4cORN-fijell ' fpecies of, 
Adanfon , his fyflem of (hells, 
Amphitrite, generic character of, 1 5 
Ancients profecute the ftudy of (hells, 3 
Animal gives form to the (hell, 112 
method of killing, 139 
Anomia, fpecies of, 43 
Area , fpecies of, 36 
Argonauta, 4 6 
Ark- (bell, fee Area, 36 
Afcidia, generic character of, 3 5 
B. 
Bivalves , terms of, defined, 
generic characters of, 
Breynius , his fyflem of (hells, 
Buccinum , fpecies of, 
Bulla, fpecies of, 
18 
22 
7 
52 
50 
Cardlum , fpecies of, 30 
Chama, fpecies of, .35 
CharaElers, generic, of teftaceous ani- 
mals, s 5 
Chiton , fpecies of, 24 
Claffification of (hells, 20 
Clto , generic character of, 15 
Cockle, fee Cardium, 30 
Colours of (hells vary, N° 88 
Colouring matter fecreted from the 
neck, 89 
proved, 90 
leeming exceptions, 91 
caufes of thefe, 92 
changes in the or- 
# gans of, _ _ 93 
difference of fluidi- 
ty in the matter, 94 
motion of the ani- 
mal, 95 
of porcelain (hells, 1 03 
affeCted by light, 108 
Conchology introduction, 1 
importance of, 2 
cultivated by the ancients, 3 
moderns, 4 
Concretions , pearls fuppofed to be 
morbid, 122 
Cone-fhell, fee Conus , 48 
Conus , fpecies of, ib. 
Cowrie , fee Cyprcea , 49 
Cyprcea , fpecies of ib. 
D. 
Da Cofia, his fyflem of (hells, 14 
D'Argenviile, his fyfte® of (hells, 9 
Dentalium, fpecies of, N° 61 
Dipper, fee Bulla , jq 
Donax , fpecies of, 31 
Doris, generic character of, 15 
Dutch method of polilhing (hells, 1 53 
Fifhery, pearl, 
F. 
140 
in Britain, 141 
in Ceylon, 142 
Gaping cockle, fee Chama , 
Geojfroy, his fyflem of (hells, 
Grooves, formation of, 
Growth of (hells, 
interrupted, 
Haliotis , fpecies of. 
Helix, fpecies of, 
H 
K. 
35 
12 
318 
80 
99 
59 
57 
Klein , his fyflem of (hells, 10 
opinion of the formation 
of (hells, 77 
Land (hells very numerous, 
12 6 
Land 
