122 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
satellite of America, with the added interest of being a stepping-stone 
to the group of islands beyond it, some of whose ornithological features 
it bears. 
Darwin, the first to study the birds of the Galapagos Islands, de- 
scribed remarkable variations among them, even those inhabiting the 
game island, that made it difficult to separate them specifically. New 
forms brought to light by recent explorations, particularly those of the 
* Albatross,” have only served as links to connect the species still more 
intimately, so that upon the Galapagos Islands there exists the most 
remarkable grading together of species known to ornithology. This is 
especially noticeable in the group of finches, in distinguishing which 
arbitrary measurements are employed, some of the smaller forms closely 
approaching Certhidea, a genus of the Cerebide. Into the gap between 
‘these (Cactornis and Certhidea) Cocornis from Cocos Island seems to fit. 
The relationship of the Cocos Island flycatcher Nesotriccus is equally close 
to Hribates inhabiting the Galapagos. In view of these facts, it is to be 
regretted that our limited stay at Cocos Island did not permit of a more 
thorough search for birds, as it is possible that other species exist in the 
elevated central part of the island which we were unable to reach. 
The island is about four miles long by three wide, its central part 
having an elevation of about 1,700 feet. It is everywhere covered with 
the densest forest. Cocoanut trees are found upon the higher slopes, 
and tree ferns abound in the ravines. No tropical forest could be more 
dense and tangled. The rainfall is doubtless great, as each ravine con- 
tains a dashing stream. It is a garden spot in comparison with the arid 
Galapagos Islands. 
I am indebted to the kindness of Mr. Ridgway, Curator of Birds in 
the National Museum, for much valuable information on the ornithology 
of the islands pf this region. 
COCOS ISLAND. 
Dendroica aureola, Gourp. 
Sylvicola aureola, Gould, Zoól. Voy. Beagle, Part III. p. 86. 
Dendraca aurcola, Salv., Trans. Zoól. Soc. Lond , Vol. IX. Part IX. p. 478. 
The two specimens of this warbler secured are nof distinguishable from the 
species (D. aureola) inhabiting the Galapagos. Only one other was seen., 
The species is more closely related to D. petechia from Jamaica than the species 
of the mainland. 
