Oryzomys brevicauda. The Garden Rat.—Widely distributed in both islands; the bulk of my captures consisted of this species, and a long series showed that there was considerable difference in the colour of the pelage.
Nectomys palmipes. Water Rat.—On the margins of the small streams this rat was always taken, and never away from water. The immature specimens were much darker and the pelage much shorter than in the adults.
Akodon urichi. Black Garden Rat.—Difficult to catch, and scarce everywhere; only taken in Trinidad.
Mus rattus. Black Rat.— This species was only secured in one cocoa shed, and had only taken up its quarters there after the Brown Rat had been poisoned.
Mus decumanus. Common House Rat.—Generally distributed wherever I collected. They were trapped in the out-door kitchens used in the West Indies, but in the day time retired to the bush to return at nightfall.
Mus musculus. House Mouse.—The foregoing remarks also apply to this species. I found both this and the House Rat living in the arrowroot fields in St. Vincent.
Heteromys anomalus. Pouched Rat.—Local in its distribution, and found at some elevation (800 feet). I had reliable information of its existence in Tobago. It is at times caught with both cheeks stuffed with seeds or corn.
Loncheres guianæ. Porcupine Rat.—In Trinidad these curious spiny rats are common on the large mangrove bushes that fringe the mouth of the Caroni river; they are to be seen lying parallel with the branches at some height above the water. They must be pugnacious in their habits, as both their ears and their tails are often found mutilated. The immature of this rodent shows very little difference in the length of the ears compared to the adult, and is in contrast with other small rodents belonging to kindred species. My friend Mr. R.R. Mole, of Trinidad, informs me that they are the chief food of the large water Pythons, and in their excreta he has found great quantities of their typical spiny bristles. I caught one of these rats in Tobago, in a tree a considerable distance from the Great Dog River; it was larger than any of the long series I obtained in Trinidad, and the basal portion of the pelage was more red in coloration.
