INDEX TO THE HISTORIA CONCHYLIORUM. 
16 
Tab. Fig. 
Gazophylacium, t. 152. f. 2.; and by Klein, at t. 9. f. 38. of his Methodus Ostra- 
colog. 
22 ^' 1 Anomia Placenta. 
226. 6l. j 
227. 62. Ostrea Ephippium: and Klein’s t. 8. f. 18. is a copy. 
228. 63. Ostrea Perna has been divided by Lamarck into two species, and this is bis Perna 
sulcata; and, according to Schroeter, it is the Ostrea semiaurita of Linneus. 
Klein’s t. 8. f. 19. and 20. are copies. 
229. 6 4. Gmelin has followed Schroeter in describing this figure as a separate species, with 
the name of Arca Jamaicensis; but it is most probably nothing more than rather 
a coarse representation of Arca candida. 
230. 64. a. Arca antiquata. 
231. 65. Bruguiere, whose references as well as descriptions are gencrally very accurate, has 
erroneously quoted this figure both for Arca barbata and for Arca fusca, and it 
belongs to the latter species. 
233. 66 . Is Arca indica: and I may here remark, that the Arca rhomboidalis of Chemnitz, 
which in the Descriptive Catalogue I have followed Gmelin in arranging as a va- 
riety, is a perfectly distinet species. 
233. 67- Arca reticulata. 
234. 68. Arca corbicula of Lamarck: and in the Descriptive Catalogue I have followed 
Gmelin in placing this species as a variety of Arca Corbula. Klein’s 1.10. f. 43. 
and 44. are copies. 
235. 69. Arca lactea. 
236. 70. In the Systema Natura;, Linneus has quoted this figure for Arca antiquata; but 
that species, in the “ Museum Lud. Ulricae,” is described with about thirty-four 
ribs, and the area between the summits flat: I therefore consider Listers t. 230. 
which is the Arca Scapha of Gronovius, to be the Arca antiquata; and the shell 
here figured, though nearly allied, is a separate species: it differs in being nar- 
rower in proportion to the length, and less rhomboidal in its form; in having not 
more than about twenty-seven ribs, which are more convex, and bifid only on 
the posterior side; the umbones also are more obliquely recurved, and the area 
between the summits is not flat, but slants considerably towards the middle. I11 
my MS. it stands with the name of Arca Cymbula, and the following are its 
synonyms: Arca antiquata of Born, Solander, and Lamarck; Arca antiquata 
Var. b. of Bruguiere; and Arca Scapha Var. of Chemnitz, vol. v. p. 205. t. 55. 
f. 549 . 
237. 71. Arca Campechensis; and Gmelins description of the species is wholly derived 
from this figure, 
238. 72. Arca senilis. 
239 . 73. Arca Pectunculus. 
— 81. Arca nummaria; and Kleirfs t. 10. f. 41. has been copied from this figure. 
240. 77. Arca pilosa. 
241. 78. Is the Arca nodulosa of Solanders MS. but I doubt whether this is more than a va¬ 
riety of Arca granosa. A specimen which I bought from Mr. Humphreys, whose 
sliells are often sold under Solanders names, differs only in being rather longer in 
proportion to the breadth, and in having the nodules much less numerous. 
Klein’s t. 10. f. 45. and 46. have been obviously borrowed from these figures. 
242. 79. Arca granosa. 
243. 74. Arca pectinata. 
244. 75. Arca rhombea. 
245. 76. Arca angulosa. 
246. 80. Arca scripta. 
247. 82. Arca Glycymeris. 
249 . 83. Car dium serratum. 
250. 84. I cannot find any reference to this figure, except one with a mark of doubt in Da 
Costa’s British Conchology, for his Trigonella Gallina: but it has much more 
the look of a shell which usually passes for a variety of Venus Meretrix, and 
which is the Cytherea petechialis of Lamarck. 
251. 8 d . Venus mactroides. 
