RENDAHL, BIRDS FROM THE PEARL ISLANDS. 3 



Total niimber of inhabitants 63, visitors in winter or during 

 migration 36. The occurence of one species, viz. Zenaida 

 auriculata Des Murs, is doubtful as it deals with a straggler. 



II. Geography. 



The Las Perlas Archipelago is the largest group of islands 

 off the Pacific coast of Central America, containing sixteen 

 larger islands and more than fifty holms and rocks. It lies 

 in the middle of the Bay of Panama, the largest of the islands, 

 San Miguel, is a distance of about twenty miles from the ne- 

 arest point of the Isthmus and about sixty from Panama city. 



Both Mr. Bångs' and Dr. Bovallius state that the rocks 

 of the islands are of volcanic origin, and the former says (Bull. 

 Mus. Comp. Zoöl. XLVI, 1905, 138) about their geological 

 history, that « from what I can gather, I infer that the Archi- 

 pelago de las Perlas has never been connected with the mainland 

 since the elevation of the isthmus and the separation of the 

 waters of the Bay of Panama from the Caribbean Sea». ^- 



As very little has been written about the geographical 

 conditions of the islands, I think it appropriate here to add 

 in a condensed form some remarks on this subject, based on 

 Dr. Bovallius' Communications. Regarding the situation of 

 the islands I ref er to the adjoining map -sketch. 



Pacheca is a mighty rock-island, about 40 to 50 m in 

 height. Its length is 1,7 km and its width 0,9 km. The upper 

 part of thisisland develops towards the east and south into 

 a gentle sloping plateau. The northern and western sides 

 descend abruptly, the former directly to the sea, the latter 

 leaving a narrow strip of shore. The plateau was thinly wooded. 



S a b o g a is one of the most beautif ul of the Pearl Is- 

 lands. Its length is 3,5 km and its width 2 km. Tropical 

 forests cover the heights intersected here and there by sunny 

 glens. Numerous bays shove in landward, bordered by lofty 

 cocoas or picturesque rock-formations. At Dr. Bovallius 

 visit the island was fairly populous. There were some maize- 

 fields, numerous cocoas and banana-trees and here and there 

 small fields with yams. The inhabitants are described by Bo- 

 vallius as probably a miscellany of Indians and Negroes, 

 thorough-bred Negroes were seen but never Indians. Saboga 

 was characterized by a very rich bird-life. 



