

806 THE MARQUIS DE FOLIN ON THE [Dec. 16, 



extreme Ritualist party in ornithology, who attempt to carry out 

 the Stricklandian code regardless of consequences, Bonaparte's name 

 would hang in terrorem over Sclater's, to be substituted for it as 

 soon as it could be proved that it certainly referred to the same 

 species; or, following the practice of the blindest followers of 

 this unfortunate innovation, Bonaparte's name would at once be 

 given the benefit of the doubt, regardless of the fact that it 

 had been extensively applied to a different species. I cannot for a 

 moment lend myself to such ornithological immorality, and must 

 look upon Bonaparte's name as one tainted for ever, and debarred 

 for the future from beiug used for any species of Thrush. 



In the fully adult male of T. hortulorum, Sclater, the general 

 colour of the upper parts is a dull slate-grey, shading on the sides 

 of the neck into a very pale slate-grey on the throat and chest. The 

 axillaries, under wing-coverts, and flanks are brilliant orange-chest- 

 nut, shading into white on the centre of the belly and under tail- 

 coverts. 



The female and immature male are undistinguishable from those 

 of T. dissimilis (Blyth). 



7. On the Mollusca of H.M.S. f Challenger ' Expedition.— 

 The C^cid^;, comprising the genera Parastrophia, Wat- 

 sonia, and C&cum. By the Marquis de Folin. With 

 a Prefatory Note by the Rev. Robert Boog Watson, 

 B.A., F.R.S.E., F.L.S., &c. (Published by permission 

 of the Lords Commissioners of the Treasury.) 



[Received November 25, 1879.] 



[The Caecidse are a group of shallow-water Mollusca, enormously 

 numerous in individuals but hitherto poor in species. As was 

 natural, very few indeed presented themselves in the ■ Challenger ' 

 dredgings ; and these I had great pleasure in intrusting to one who 

 has so specially made the group his study as the Marquis de Folin. 

 His acquaintance with the subject in general, and his own vast 

 collection of specimens gathered from every quarter of the globe, 

 are the pledges that in what he has now produced nothing known 

 on the subject has been overlooked ; and even those who may 

 hesitate to accept in full his classification will recognize both the 

 general value of this monograph, and the extraordinary perfection 

 with which he has delineated the specimens. 



Robert Boog Watson.] 



1. Parastrophia challengeri, n. sp. 



St. 186. Sept. 8, 1874. Lat. 10° 30' S., long. 142° 18' E. 

 Wednesday Island, Cape York. 8 fms. Coral-sand. Temperature 

 of sea at the surface 77°'2 F. One specimen. 



Testa minuta, tubularis, tricurvata, subopaca, alba, nitida, minu- 



