388 DB. H. L. JAMESON ON THE [A-pr. 16, 



Species 19. Maegaeitieeea imbricata. 



Avicula imbricata, Eeeve, 1857, sp. 11 ; Philippines. Type in 

 B M. ( = M. vulgaris, fide Cooke, 1886.) 



'Avicula muricdta, Eeeve, 1857, sp. 12 ; Philippines. Type in 

 B.M. ( = ^1/. vulgaris, fide Cooke, 1886.) 



Types, figures, and descriptions quite inseparable. Both species 

 may well be the young of the White Banda. 

 Species 20. Margaeitifera ghemnitzii. 



Avicula chemnitzii, Philippi, 1849, p. 19 ; China Sea. 



Chemnitz, 1785, vol. viii. tab. 80. fig. 720; Tranquebar (ref. 

 Vhi\\Tppi): '? = M. vulgaris. 



Avicula (Meleagrina) chemnitzii, Philippi, Dunker, 1872, p. 15, 

 pi. 3. fig. 5 ; China Sea. 



Dunker suggests that 31. lentiginosa (Eeeve) = i/. chemnitzii 

 (Philippi). 



Species 21. (Unlocalized.) 



Margaeitieeea cetra. 



Avicula cetra, Eeeve, 1857, no. 28 ; no loc. Type in B.M. 

 Species 22. Margaritieera pitcairnensis, n. sp. 



For Avicula pica, Gould, Eeeve, 1857, sp. 71 ; Pitcairn Island. 

 Type in B.M. 

 '(Not Avicula pica, Gould, 1852, p. 443, pi. 39. fig. 549.) 



Type sp. Mus. Cuming, B.M. 



I cannot agree that Eeeve's Avicula pica Gould, from Pitcairn 

 Island, is the same species as that figured and described by Gould 

 from Samoa. Eeeve's type specimen is a dwarfed thick-shelled 

 example of a mollusc that normally resembles M. vulgaris very 

 closely. The Mus. Cuming specimens, from among which my 

 type is selected, and which are probably paratypes of Eeeve's 

 species, are very like some specimens of Australian and New Guinea 

 Lingahs. In the absence of evidences of iutergradation, I am 

 treating this Pitcairn shell as distinct from the latter. If further 

 material is procured, it may be found to be a local race of 

 M. vulgaris. 



Size and form as in M. vulgaris, but with the processes of the 

 lip-margin thicker and more rounded, resembling those of M. lurida 

 Gould and M. panasescew. sp., rather than those of the Liogah 

 shells. The transverse dark and light marks on these processes, 

 so characteristic of M. vulgaris, are absent. The ground-colour of 

 the shell is \\hite, with a number of radial bands of dark red 

 or purple-brown, which, as in M. vulgaris, are quite different in 

 their number and relations in different individuals. Interior of 

 the lip white, with red or purple blotches. Nacre lustrous, slightly 

 golden in tint. The characters of the lip-processes and the 

 prevailing white ground-colour distinguish this shell from typical 

 M. vulgaris. The white ground-colour occurs occasionally in the 

 Trobriand Island M. vulgaris and in Lingahs from other localities. 



