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Show 352 MR. R. B. SHARPE ON THE GENUS ALCYONE. [May 13, Having already (P. Z. S. 1868, p. 587) treated of the genus Ceyx, I propose in the present paper to discuss the genus Alcyone, which has only three toes, and is otherwise closely allied to Ceyx. The genus Alcyone was founded in 1837 by Swainson (Classif. of Birds, ii. p. 336), and at present contains seven species. The two most distinct and clearly characterized are Alcyone pusilla and A. cyanopectus; but the other five are very closely allied and hard to distinguish. I believe that the following synoptic table will materially assist in their identification :- A. Torque pectorali lazulino 1. A. cyanopectus. B. Torque pectorali nullo. a. Abdomine rufo. a'. Eostro robustiore. a". Supra saturate ultramarina 2. A. lessoni. b". Supra laitissime ultramarina 3. A. affinis. b'. Eostro tenuiore. a". Eostro breviore: pileo nigro indistincte fasciato 4. A. diemensis. b''. Eostro longiore: pileo haud fasciato. a'". Hypochondriis rufis 5. A. azurea. b'". Hypochondriis pulcherrime ul-tramarinis 6. A. pulchra. b. Abdomine albo 7. A. pusilla. The first on the above list, Alcyone cyanopectus, serves to connect the genus Alcyone with Ceyx, as it is very closely allied to Ceyx philippinensis, Gould; and, on the other hand, another link is discovered in Alcyone pusilla and Ceyx solitaria, both of which species are closely allied. The principal difference between the genera Ceyx and Alcyone is in their habits. Whereas the Ceyces are almost entirely insectivorous, the members of the genus Alcyone feed almost entirely on fish. The geographical distribution of each genus is also in favour of their direct affinity. Ceyx is an Indian genus strictly speaking, extending all over the Indian peninsula and Malayasia, being also distributed over the Malay archipelago, where, however, a different form of the genus (with bright blue back) is met with. On the other hand, Alcyone is essentially a typical Australasian genus, being widely distributed over the whole Australian continent, and thence extending northwards, through the Austro- Malayan subregion, to the Philippines. In these islands the aberrant species Alcyone cyanopectus occurs; and in every respect as regards plumage this species is a true Ceyx. In form of bill, however, it is an Alcyone-although, but for the distinct pectoral band and blue flanks, it might be mistaken for Ceyx philippinensis. M y friend Dr. Salvadori has written to m e, calling in question the propriety of m y placing this latter bird in the genus Ceyx; but in m y opinion the species really belongs here. Alcyone cyanopectus should probably also be included in the genus Ceyx as an aberrant species forming the point of union between the two genera, and I should not be at all surprised to find this view adopted by some future systematise But no satisfactory conclusion can be obtained until we know more of the habits and geographical distribution of these two |