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Show 1867.] THE BIRDS OF T H E LOWER AMAZONS. 593 Fam. LARIDA. 280. STERNA MAGNIROSTRIS, Licht. Mexiana. 281. STERNA SUPERCILIARIS (Vieill.). Rio Tocantins. 282. RHYNCHOPS MELANURA, SW. Mexiana. Having thus concluded our list of species, we proceed to consider what conclusions can be drawn from it as to the general character of the avifauna of the localities whence they are derived. Of the whole number of 282 species, 48 are from the Rio Negro, and, as far as our information goes, are not found in the Lower Amazons district. From this part of the series, presenting us as it does with such an insignificant portion of the whole ornis, it would be useless to attempt to draw any further conclusion than that the large majority of the species recorded from this region are Guianan forms. Of tbe 48 Rio Negro species, 37 are certainly likewise found in Guiana. The remaining 11 are believed to be either peculiar to the Rio Negro or intruders from the Upper Amazonian district. These are- 1. Ramphoccelus nigrigularis. 7. Chordeiles rupestris. 2. Pithys leucaspis. 8. Topaza pyra. 3. Pipra filicauda. 9. Eucephala hypocyanea. 4. cyaneocapilla. 10. Capito amazonicus. 5. Cephalopterus ornatus. 11. Psophia ochroptera. 6. Pharomacrus pavoninus. But these exceptions weigh little in the balance when we consider the presence on the Rio Negro of such marked Cayenne types as Gymnoderus fcetidus, Gymnocephalus calvus, Rupicola crocea, Xipholena pompadora, &c. Let us now, therefore, turn to the portion of the collection from the vicinit}' of Para and the Lower Amazons, and see what results can be derived from its examination. The whole number of species obtained in these localities was 242, two of which cannot be satisfactorily determined at present. The remaining 240 may be analyzed as follows:- 1. Species of wide range, belonging to Cayenne, j „„ Para, and South-east Brazil J 2. Species common to Para and Cayenne only,"", 40 (16 per cent, of whole number); and | species ranging west and north-west into V 88 (about 61 per cent.)") the Upper Amazons, Venezuela, N ew Gra- j nada, and Central America, 48; together ...) . 3. Species common to Para and South-east Brazil 15 (about 10 per cent.) [ 4. Species common to Para and Upper Amazons... 18 (about 12percent.) j 5. Species found in Para alone 23 (about 17 per cent.) j 240 The 96 wide-ranging species, which amount to about 40 per cent, of the whole, comprise members of all orders, but are mostly PROC. ZOOL. Soc-1867, No. XXXVIII. |