with lightning speed when approached. Mr. Bates tells us that it is the males only of the different species which are brilliantly colored, the females being plainer and often so utterly unlike their partners that they are generally held to be different species until proved to be the same. The observations of this admirable naturalist on other points in the history of the butterflies of the Amazons, are highly important and deeply interesting. We must recur to this subject by-and-by. We cannot yet tear ourselves away from these forests of Pará. We can well understand the intense interest with which Mr. Bates visited these different scenes month after month, in different seasons, so as to obtain something like a fair notion of their animal and vegetable productions. It is enough to make a naturalist's mouth water for a week together to think of the many successful strolls which Mr. Bates took amid the shades of these forests. For several months, he tells us, he used to visit this district two or three days every week, and never failed to obtain some species new to him of bird, reptile, or insect: "This district," he says, "seemed to be an epitome of all that the humid portions of the Pará forest could produce. This endless diversity, the coolness of the air, the varied and strange forms of vegetation, the entire freedom from mosquitoes and other pests, and even the solemn gloom and silence, combined to make my rambles through it always pleasant as well as profitable. Such places are paradises to a naturalist, and if he be of a contemplative turn there is no situation more favorable for his indulging the tendency. There is something in a tropical forest akin to the ocean in its effects on the mind--man feels so completely his insignificance there and the vastness of nature. A naturalist cannot help reflecting on the vegetable forces manifested on so grand a scale around him."