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Show 1870.J MR. O. SALVIN ON THE BIRDS OF VERAGUA. 177 get 703 species as an approximate estimate of the number of species included in the whole bird-fauna of Central America south of the Lake of Nicaragua. Considering how imperfectly several orders must be represented, we shall certainly not be estimating the whole number too highly if we place it at 720 species. The superficial area of Central America south of the Lake of Nicaragua is about 38,000 square miles, or an area about equal to two-thirds that of England and Wales; yet in this limited extent of country we find a considerably greater number of birds than in the whole of Europe ; in fact, the number nearly equals that of the whole continent of America, north of Mexico. The names of the places visited by Arce in his collecting-expeditions are Calovevora, Calobre, Chitra, Boqueti de Chitra, Castillo, Laguna del Castillo, and Cordillera del Chucu. Many of these places are unmarked on the best map I can find, viz. that of Codazzi, published in Bogota in 1864 • but from Arce's letters I gather they are all situated in one district, near Calobre and Santiago de Veraguas, and are in what is called El Mineral de Veraguas. I also infer that Arce's collecting-ground has been almost, if not entirely, on the southern, or that slope of the main Cordillera which stretches towards the Pacific Ocean. The later collections, which bear the localities Mina de Chorcha, Bugaba, and Volcan de Chiriqui, were all made since Arce reached David, the principal village of the district of Chiriqui. These collections, too, were formed on the southern slope of the Volcano, the highest point reached being about 6500 feet above the sea-level. I hope yet to be able to fill in, on the accompanying map (Plate XVII.), all the names of the places above mentioned. In the meantime, those already supplied will give the general position of the districts explored. The publication by Mr. Lawrence of * A Catalogue of the Birds found in Costa Rica' (Ann. Lye. N. Y. ix. pp. 86-149) supplies an important addition to our knowledge of the isthmian avifauna, and enables m e to review in a more complete manner the generalizations I ventured to make respecting the relationship the birds of Veragua bear to those of the surrounding countries. In m y former paper I stated that the portion of Veragua then explored showed that, as regards its birds, a rather stronger numerical affinity was exhibited towards Panama than towards Costa Rica, and a slightly closer connexion with the more northerly portions of Central America than with the adjacent southern continent. But, owing to the incompleteness of our knowledge at the time of the bird-fauna of Costa Rica, I somewhat mistrusted the result shown by the facts at m y disposal. Partly owing to the exploration of the district of Chiriqui, and partly to the large amount of distributional knowledge acquired by the publication of Mr. Lawrence's list, the relationship between bird-life in Veragua and in the adjoining countries now assumes to a great extent a different aspect. The bonds of union with Costa Rica are drawn much more close |