16 
SpATHA COMPRESSA, m. 
Testa oblonga, compressa, solida, epidermide nigricante, sericeo- 
nitente, subtomentosa; umbones parvi, approximati ; margo ven- 
tralis rectus, margo anticus rotundatus, posticus perpendicula- 
riter subtruncatus ; cardo edentulus, in valva dextra callo parvo 
prominulo munitus, in valva sinistra paulisper emarginatus ; 
impressiones musculares profunde, antice dua@, accessoria 
magna subquadrata; postica unica, ovata; facies interna 
cerulescenti-margaritacea, centrum versus flavescens. 
Long. 87, alt. 44, diam. 24 mill.; vertices in 2 longitudinis siti. 
A specimen purchased for the British Museum from a dealer, 
together with other Siamese shells, is noted as coming from ‘‘ Khao- 
kho, north-east of Pakpriau in Siam.” 
Spatha is regarded by most authors as a genus peculiar to the 
African region; but there is besides the above, another species in the 
British Museum marked as coming from Manilla, and allied as nearly 
to Spatha rubens as Spatha compressa is to S. wahlbergi. 
Deshayes, in the second edition of Lamarck’s work, points out the 
depth and size of the muscular impressions, and more particularly of 
the accessory one on the fore half of the valve, as the only character 
by which the shell of Spatha might-be distinguished from that of 
Anodonta. This character, coinciding with the very striking re- 
semblance to the South African species of Spatha, named above, 
leaves me no doubt that this shell should be placed in the same 
genus. 
Cyrena (subg. CorsicuLA) oRIENTALIS, Lam. Desh. Cat. Brit. 
Mus. p. 227? 
Shell much swollen, subequilateral, with regular distant elevated 
ribs, gradually becoming obsolete on the hinder end; umbones very 
blunt, thick, in great extent decorticated. Teeth of the hinge simple, 
lateral teeth nearly equal in length, curved and striated through the 
whole of their length. 
Alt. 20, long. 214, diam. 16 mill. 
III. Sea-sHELLs. 
We find in the above-named work of Favanne two species with the 
epithet ‘ Siamoise,”’ namely, vol. ii. p. 9, “la Couronne Siamoise,” 
without figure; according to the author’s words, nearly allied to 
Turbo argyrostomus, L., but distinguished by seven rows of thick 
and elevated girdles. The other, ibid. p. 274, “la Natice Siamoise,” 
pl. 11. f. D 5, appears to be Natica lineata, Lam. It should be stated 
that Favanne mentions China, not Siam, as the locality of both of 
them ; but we may conclude, from the French names quoted above, 
which, without doubt, were then used in the collections of the 
amateurs, that those shells were originally brought from Siam to 
France. 
We cannot say the same of the ‘‘ Siamoise @ collier,” the account 
of which immediately follows that of the above species of Natica, 
