BANGS: VERTEBRATA OF GORGONA ISLAND. 89 



The fauna of the island is extremely poor. There are very few binls, 

 either in numbers or in species ; in a day's tramp perhaps from six to ten 

 birds may be seen. Mammals also are scarce, and with the exception of 

 the spiny rat, no small rodents were found. Land crabs swarmed and 

 proved a great annoyance, eating up or injuring most of the spiny rats 

 cau"-ht ; they also carried off the bait about as soon as a trap was set. 

 Snakes of several species were not uncommon, and two small frogs were 

 abundant in the woods. The waters around the island swarmed with 

 fish, and wliales were very abundant, the vicinity of the island being a 

 favorite feeding-ground during the summer months. 



At the southwestern extremity of the island there is a peninsula about 

 a mile long, called Gorgonilla ; at high water Gorgonilla is essentially an 

 island. Here boobies of two species and man-o'-war birds breed in great 

 numbers. At the time of my visit they were not nesting, though they 

 were present in considerable numbers, roosting or resting between the 

 times they were at sea hshing. 



III. Mammalia. By Outram Bangs. 



Apart from two bats, Mr. Browji found but three species of mam- 

 mals, — a monkey, a spiny rat, and an agouti. The first two are peculiar 

 and new ; the agouti, however, I am not able to distinguish from Da^y- 

 2)roda variegata, though the only specimen taken is too young to be 

 identified with absolute certainty. 



Mr. Brown feels confident that no small terrestrial mammals occur in 

 Gorgona, not only because he trapped assiduously without getting any, 

 but because the rain-soaked condition of the ground and underbrush 

 throughout the year seems to preclude any chance of their occurrence. 



Dr. Glover M. Allen has very kindly helped me identify the bats. 



All the measurements are in millimetres, and the colors are according 

 to Eidgway's nomenclatm-e. 



OCTODONTIDAE. 



1. Proechimys gorgonae, sp. nov. 



Type. — Mus. Comp. Zool. No. 10,828, old ad. (J, Gorgona Island, July 2, 1904. 



Seven specimen?, adults and youncr, June 2ri to July 2, 1904. 



Characters. — Apparently nearest P. centralis panamensis Thomas, but very 

 different in color, beinf,' very dark above and with the under parts not wholly 

 white. Skull very similar to that of P. centralis panamensis, from which it can 



