MUSEUM OF COMPARATIVE ZOOLOGY. 69 
grasses and bushes on Charles and Chatham Islands, and must have 
supplied the insectivorous birds with abundant food. 
A few reptiles were collected at the Galapagos, Cocos Island, and 
Malpelo. 
The only tortoise we obtained was found on Duncan Island by Mr. 
Townsend ; we kept it on board the “ Albatross ” as far as Guaymas, and 
from there it was shipped to Washington, where it arrived safely. 
The well worn tortoise tracks which Darwin saw on landing at Chat- 
ham Island, leading to the springs, which are situated on the larger 
islands towards the central parts and at a considerable elevation, are 
still quite marked on Charles Island. I saw no trace of them either 
on Chatham or on Duncan, on the parts of the islands which I exam- 
ined. On Chatham, the tortoises, I was told by Mr. Cobos, have long 
since disappeared. According to Darwin, “it is said that formerly 
single vessels have taken away as many as seven hundred of these 
animals,” so that the disappearance of the turtles is not astonishing ; 
and they and the terrestrial Amblyrhynchus, which also serves as food, 
have become comparatively rare. We also collected at Duncan Island 
a few specimens of the aquatic Amblyrhynchus. 
Sharks are very abundant throughout the waters of the Galapagos, 
and they, as well as the strong currents sweeping through the passages 
which separate the islands, may play an important part in checking the 
migration of animals from one island to another. We saw small sharks 
in great numbers at all our anchorages. Captain Tanner says that, in 
1888, “the anchorage at Wreck Bay was infested with small sharks, 
which were taken by dozens until the fishermen tired of the sport.” 
A few specimens of rocks were also brought together from the dif- 
ferent islands we visited, and such plants collected as it was possible 
to get during our short stay on shore. 
Tre Conan SAND Bracues OF THE GALAPAGOS. 
I obtained from Mr. Cobos a piece of the so called sandstone said to 
oceur on Indefatigable Island, and which of course I was most anxious 
to see, as the occurrence of true sandstone would have put quite a differ- 
ent face on the geological history of the Galapagos from the one usually 
received. This I found to be nothing but coral rock limestone, either a 
breccia or slightly oölitie, identical with the formation found back of 
the beach at Wreck Bay on Chatham Island. I found there an old coral 
rock beach, extending on the flat behind the present beach, composed 
