with the knuckles bent at an acute angle, and thus mounted to the top with the greatest facility. Although seeming to prefer insects, it ate all kinds of fruit, but would not touch raw or cooked meat, and was very seldom thirsty. I was told by persons who had kept these monkeys loose about the house, that they cleared the chambers of bats as well as insect vermin. When approached gently, my Ei-á allowed itself to be caressed; but when handled roughly, it always took alarm, biting severely, striking out its little hands, and making a hissing noise like a cat. As already related, my pet was killed by a jealous Caiarára monkey, which was kept in the house at the same time.
I have mentioned the near relationship of the night apes to the Sai-mirís (Chrysothrix), which are amongst the commonest of the ordinary monkeys of the American forests. This near relationship is the more necessary to be borne in mind, as some zoologists have drawn a comparison between the Nyctipitheci and the Microcebi, Nycticebi, and Loris, nocturnal apes of the Lemur family inhabiting Ceylon and Java, and it might be erroneously inferred that our American Ei-ás were related more closely to these Old World forms than they are to the rest of the New World monkeys. The Nycticebus of Java has also large nocturnal eyes, short ears, and a physiognomy similar to that of our Nyctipitheci; resemblances which might seem to be strong proofs of blood-relationship, but these points are fallacious guides in ascertaining the genealogy of these animals; they are simply resemblances of analogy, and merely show that a few species belonging to utterly dissimilar families have been made similar
