IN a celebrated lecture on "Snakes," given by Mr. Ruskin at the London Institution in March 1880, he introduced his subject with the three considerations: "What has been thought about them?" "What is truly known about them?"-extremely little, as he suggested;-and, "What is wisely asked about them, and what is desirable to know?"The three questions exactly agree with the object of my work, this chapter especially; and I will invite my readers to seek in their own minds the answer to the first question, which will also furnish a solution to the second, and, I trust, incite some interest in the third.