Several American naturalists have contributed interesting accounts of this last species, known as the ‘Bull’ or ‘Pine snake,’ or ‘Pilot snake,’ the largest of the N. American Colubers. It was this species (_Pituophis melanoleucus_) whose actions Mr. Sam. Lockwood described as mystic circles, and its activity as almost equal to that of the ‘Racer’ (_American Naturalist_, vol. ix. 1875). But it is called the Bull snake because it ‘roars like a bull.’ Bartram went so far as to say like thunder! ‘Said to hiss like thunder,’ or ‘resembling distant thunder,’ is the cautious testimony of Holbrooke, who adds, ‘but I never heard it, though well acquainted with it.’ Mr. Lockwood minutely described one in his possession. In reading his account we can but notice the similarity of action between this ‘Bull snake’ and the African vipers in ‘puffing,’ though regarding the nature of the sound, the writer positively affirms that ‘there is nothing sibilant in this blowing, not the slightest hiss about it.’ Mr. Lockwood records his experience of several that he had seen and heard, and of a fight between one and a rat. ‘Now began that fearful blowing. The snake slowly fills its lungs with air, and then expels it with a bellowing sound that is really formidable.’ And again, in the same volume, in reference to the former account, he says: ‘As there noted, the _Pituophis_, when alarmed or enraged, slowly inflates itself with air, thus nearly doubling its normal size along its entire length, except the tail. It then slowly expels the air with its own peculiar sound.’ He recalls his boyish terror on once hearing this sound, which came upon him suddenly in a field, ‘like the restrained roaring of a bull.’ This was in New Jersey; but the _Pituophis_ family extends to the Western States, and to the Rocky Mountains, where ‘Bull snakes’ are frequently seen. In the reports of the United States Exploring Expeditions, mention has been made of the prairie Bull snake, and of others in Nebraska and as far west as California.