24 JOURNAL OF CONCHOLOGY, VOL. 12, NO. I, JANUARY, I907. 



ocean was here spread out. Hence, both in space and tune, we 

 seem to be brought somewhere near to that great fact— that mystery 

 of mysteries — the first appearance of new beings on this earth. 



Of terrestrial mammals there is only one which must be considered 

 as indigenous, namely a mouse . . It belongs . . to a 

 division of the family of mice characteristic of America. At James 

 Island there is a rat sufficiently distinct from the common kind to 

 have been named, . . but as it belongs to the old-world 

 division of the family, and as this island has been frequented by 

 ships for the last hundred and fifty years, I can hardly doubt that 

 this rat is merely a variety, produced by the new and peculiar 

 climate, food, and soil, to which it has been subjected. 



Of land birds I obtained twenty-six kinds, all peculiar to the 

 group and found nowhere else, with the exception of one lark-like 

 finch from North America. The other twenty-five birds consist first 

 of a hawk, curiously intermediate in structure between a buzzard and 

 the American group of carrion-feeding Polybori . two owls 

 a wren . three tyrant flycatchers (two of them species of 

 Pyrocephalus, one or both of which would be ranked by some 

 ornithologists as only varieties) and a dove — all analagous to, but 

 distinct from, American species. A swallow, which though differing 

 from the Progne purpurea of both Americas, only in being rather 

 duller coloured, smaller, and slenderer, is considered by Mr. Gould 

 as specifically distinct . . three species of mocking thrush — 

 a form highly characteristic of America. The remaining land birds 

 form a most singular group of finches. All the species are peculiar 

 to this archipelago . . one might fancy that from an original 

 paucity of birds one species had been taken and modified for 

 different ends. In like manner it might be fancied that a bird 

 originally a buzzard had been induced here to undertake the office 

 of carrion feeding. 



Of waders and water birds only three are new species, one gull 

 is peculiar, but allied to one from South America." 



After describing the reptiles of the archipelago Darwin proceeds 

 to state " the fifteen different kinds of sea-fish which I procured here 

 are all new species. . . Of land shells I collected sixteen kinds 

 (and two marked varieties), of which with the exception of one 

 Helix found at Tahiti, all are peculiar to the archipelago : a single 

 fresh-water shell (Paludina) is common to Tahiti and Van Diemen's 

 Land. ]\'Ir. Cuming, before our voyage, procured here ninety species 

 of sea-shells, and this does not include several species not yet specific- 

 ally examined, of Trochus, Turbo, Monodonta, and Nassa. He has 

 been kind enough to give me the following results. Of the ninety 

 shells no less than forty-seven unknown elsewhere. Of the forty- 



