47 143 
Commonly distributed between Koh Rin and Koh Kong. 1—30 fathoms, mud, 
sand, gravel, shells and stones. The specimens gathered were almost all young 
individuals. 
Long. 10—38 mm., alt. 10—32 mm. 
Distribution: — Malacca, Singapore, Madras, Ceylon, Palk’s Strait, Gulf of 
Manaar,’ Maldives, Persian Gulf, Gulf of Aden, Red Sea, Suez (since the opening of 
the Suez Canal this species has wandered into the Mediterranean. There are typical 
examples from Alexandria and Malta in the British Museum.”), Mauritius, Bazaruto 
Isl., Durban. — Philippines, Japan (?), Flores, Sandwich Isls., Torres Strait, North 
Australia, East Australia (as far as Sydney), West Australia (as far as Sharks Bay), 
New Guinea, New Zealand (GouLp). 
I have followed H. L. JAmMEson (1. c.) in his opinion regarding P. vulgaris, 
Schum., although I feel convinced that several of the species in his “Section c” are 
nothing else but varieties of this species. ScHuMACHER’Ss original specimen is in 
the Zoological Museum of the University of Copenhagen, and I can only confirm 
JAMESON’S opinion that P. vulgaris, Schum., is identical with P. fucala, Gould. 
P. vulgaris, Schum., has had numerous names given to it, owing to its variability 
in shape and colour. Thus A. H. Cooke*® enumerates the following of RrEEvE’s 
species as identical (the original specimens in the “British Museum” were at his 
disposal): — imbricata, muricata, lentiginosa, occa, fimbriata, anomioides, aerala, 
irradians, and nebulosa, Conr. JAMESON (who has had the same specimens for 
examination) gives: — occa, Reeve, aerata, Reeve, perviridis, Reeve, varia, Dunker, 
and badia, DuNKER, as synonyms of P. vulgaris, Schum. G. B. SowEerBy* believes 
that Avicula flabellum, Reeve,® and A. lacunata, Reeve, may be added to these. 
A. Martensi, DuNkEnR,° is also, no doubt, nothing but a form of the present species. 
G.F. AnGas‘ considers A. placunoides, Reeve, a variety of fimbriata, Reeve. 
1 For details comp. L. G. Srurat, VHuitre perliére. Paris 1901. — E.Im TuHurn, Sketch of the 
Ceylon Pearl Fishery of 1903. (Spolia Ceylanica, I. Colombo 1903). — J. Horne_i, The Biolog. Results 
of the Ceylon Pearl Fishery of 1904. (Reports from the Ceylon Marine Biological Laboratory No. 1, 
Colombo 1905. — J. Catcorr Gaskin (Proc. Zool. Soc. London, 1906, p. 803), A Memorandum on the Pearl- 
shells in the Persian Gulf. — Epc. THursron, Notes on the Pearl and Chank Fisheries and Marine Fauna 
of the Gulf of Manaar, Madras 1890. — Report on the Pearl Oyster Fisheries of the Gulf of Manaar, 
by W. A. HerpMan. 1—5. London 1903—6. — P. vulgaris, Schum., is fished here on a large scale for 
the sake of the pearls. 
2 H. L. Jameson (1. c. p. 385) and VasseL, Sur la Pintadine du Golfe de Gabes (Comptes-rendus. 
Assoc. franc. p. lavancem. d. sc., 1896, pp. 458 —66). 
’ The Annals and Magaz. of Nat. Hist., vol. XVII, 1886, pp. 186—37. 
* Appendix to Marine shells of South Africa, Lond. 1897, p. 27. 
5 This is a form from Venezuela and A. H. Cooke says (1. c. p. 137) that the type in the British 
Museum differs from A. fucata, Gould. 
° Index molluscor. mar. Japon. Cassel 1882, p. 229, pl. 10, figs. 7—8. 
* Proc. Zool. Soc. London, 1867, p. 930. 
