550 ADDITIONS AND CORRECTIONS 
Tablet 498 containa, with the fragments of the broken valve, a 
rather larger, opposite valve, also broken. This has no car- 
dinal tooth; the ligament remains, filling the space under 
the umbo; and the concentric undulations are fainter. 
Lablet 503. Instead of the fragment, is a perfect valve since 
found, with the ligament pit normal; whether conspecific 
with the other valve is doubtful. 
Page 115, line 15, for “irregular,” read “regular.” 
Species 166, add to synonyms, “Comp. Anodonta glauca, Vai. 
fec. Obs. vol. ii. p. 236, pl. 50, f.2.” Dr. Gray thinks it 
probable that the species is an Iridina. 
Page 124. Tablet 2530 contains a small pair of “No. 695, 
CRENELLA——, sp. ind.”’; in shape somewhat resembling 
Modiola Braziliensis, but with the epidermis hairy on the 
posterior part, where it lies in radiating lines, while it 1s 
concentric on the anterior, decussated towards the middle. 
Found on Spondylus ealeifer. Long. °075, lat. *C3. 
Page 131, lines 28, &c., read ‘Tablet 605 contains the original 
sp. of Leiosolenus spatiosus, presented by R. D. Darbishire, 
Esq. One since found measures long. 2,°'3, lat.°7, alt. °7. 
Species 184, add to synonyms, “Var. ?=Arca trapezia, Desh. in 
Rev. Cuv. Soc. 1839, p. 358 :—Guér. Mag. Zool. 1840, pl. 21. 
San Blas.” 
Page 148, last line, &c., for “Discoporea” read *‘ Defrancia.” 
Species 204 should stand as ‘“MARGARITIPHORA FIMBRIATA, Dkr. 
Avicula (Meleagrina) fimbriata, Dkr. in Zeit. f Mal. 1852, 
p. 79, no. 13. Central America.” 
Species 212. Ostrea Canadensis is distinct, teste Gould. 
Species 214, 6b. The examination of additional specimens con- 
firms the opinion that Ostrea PALMULA is a distinct species. 
Species 220 is probably a Naranio: See page 529. 
Page 176, line 8 from bottom, after “f.1,” add “a, 6.” 
» 177, line 3 from bottom, add ‘‘p. 247, pl. 56, f. 1, a, 6.” 
Species 240. Add “=Siphonaria equilorata, [Rve. quasi] 
Gray ms., Rve. Conch. Ic. pl. 4, sp. 15, f. 15 a, b. Vide Brit. 
Assoc. Rep. 1857, p. 290, note *.” 
Species 242. Add to Hab. “‘Sandwich Islands, Nuttall.” 
Species 255 should he ““Mac-ANDRER.” 
Page 199, dele line 2 from bottom. Dr. Gould’s shell is the 
