According to Holbrook, this reptile feeds upon young rabbits, squirrels, rats and other small mammals. It lays its eggs in August, and the young are hatched at once, and are capable of seeking their own food.
In captivity as well as under natural conditions the Mottled Rattle-Snake is an excessively irritable species. “The noise of the wind,” says Brehm, “or even the distant view of a man or animal, are sufficient to irritate it. It then coils itself up in a spiral, and places its head and tail in the centre of the disc thus formed, in a state of absolute immobility. After a short interval the creature raises its head to a height of about 8 to 12 inches above the ground, curves its neck in the shape of an S, and elevates its tail into a vertical position and shakes it vigorously, whereupon the strident noise caused by the rattle is heard. So rapid are the movements communicated by the Crotalus to its tail that they can scarcely be distinguished. So long as the Crotalus believes itself menaced it remains in the position that we have just described, and continues to sound its rattle. If one withdraws from the irritated snake, the sound gradually lessens and ceases, to begin again more vigorously when the reptile is once more approached.”
The bite of these snakes is exceedingly dangerous. Pigs wage an inveterate war against them and devour them.
At the Pasteur Institute at Lille, I have kept several of these reptiles in captivity for eighteen months and longer. They invariably refused their food, and I always had to resort to artificial feeding. They are easily capable of withstanding a prolonged fast.
(4) C. durissus (Common Rattle-Snake).—7 or 8 longitudinal series of scales between the supraoculars, 3 or 4 series of scales between the eye and the labials; 13-16 supralabials; scales in 25-29 rows, dorsals strongly keeled; ventrals 169-181; 24-32 subcaudals.
Fig. 74.—Crotalus scutulatus (Texas Rattle-Snake). (After Baird and Stejneger.)
Colour pale greyish or brownish, with a dorsal series of large blackish rhomboidal spots; a yellowish cross-line between the eyes; snout blackish; end of tail usually black; belly yellowish, more or less spotted with brown or black.
Total length may be as much as 8 feet (2,400 millimetres).