292 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Dr. Theodor Wolf, State Geologist of Ecuador, and by Com- 

 mander Cookson of the "Petrel"; in 1884, by Lieutenants 

 Chierca and Marcacci; in 1888, by L. A. Lee of the "Albatross 

 Expedition"; in 1891, by Prof. A. Agassiz on the "Albatross," 

 also by Prof. Geo. Bauer and his assistant; in 1898-99, by 

 Messrs. Snodgrass and Heller of the Hopkins-Stanford Expe- 

 dition; and finally in 1905-06, by the Expedition of the Cali- 

 fornia Academy of Sciences. The last expedition had, besides 

 the navigator and the first mate and steward, a staff of eight 

 men representing the departments of Zoology, Entomology, 

 Conchology, Botany, Geology and Palaeontology. A full year, 

 of the seventeen months of the Expedition, was spent in the 

 Archipelago, and although much time was lost by reason of th6 

 little two-masted schooner "Academy" drifting about the 

 Pacific in calm weather, all the islands and many of the "mere 

 rocks" of the group were visited at least once, and a number, 

 several times, and from different points and during various 

 seasons. Thus the Expedition, equipped for the special purpose 

 of studying and collecting specimens of natural history, was 

 able to bring together a far larger and more varied assemblage 

 of specimens than was collected perhaps by the sum total of all 

 the previous expeditions to these islands. It is only fair to 

 bear in mind, however, that a number of the earlier expeditions 

 were handicapped by lack of time, equipment, and sufficient and 

 capable collectors ; nevertheless, the results of their labors are 

 very creditable when we consider the paucity of the Galapagos 

 fauna, the general rough character of the country, and the fact 

 that in some cases, the collecting and studying of specimens of 

 natural history was but a secondary or incidental matter. 



The zonal divisions of the fauna and flora of the Archipelago 

 are very interesting. The plant zones on the windward (S. E.) 

 side of the more lofty islands are often quite distinctly defined 

 and can be observed from several miles at sea. The Zoological 

 regions conform in a greater or less degree to those of the flora. 

 The south and southeast sides of Indefatigable Island, show 

 these zones very nicely,^ and a brief discourse on them will give 



^ While the zones may be distinct on the weather side of an island, the opposite or 

 dry side of the latter displays no such well-defined areas, hence the arid belt de natura 

 extends much higher up on that side, while the humid areas are forced far up the 

 slopes and are of quite limited extent, if at all present. 



