COBKAS AND KATTLESNAKES 



349 



rat ran over the snake several times, and greatly 

 annoyed it. The snake endeavored to get away 

 from its disreputable associate, but in vain. 



At last the rat flew at the Rattler, and bit 

 him severely on the lips! This was too much 

 to be endured. In a great rage the snake 

 drew back, seized the body of the rat in its wide 

 jaws, and held on while it drove its fangs through 

 the tough skin of the rodent, and far into its 

 body. After one could have counted ten, the 

 rat was released; and thirteen minutes later it 

 was dead. 



Species of Rattlesnakes. 



Fourteen valid species of Rattlesnakes are 

 found in North America, one in South America, 

 and there are none elsewhere. Our most promi- 

 nent species are as follows: 



their young alive, the normal number being be- 

 tween nine and fourteen. As soon as an infant 

 Rattler bursts the thin transparent sac in which 

 it is born, it is ready to coil and strike. Even at 

 birth it is fully equipped with poison and fangs. 

 Wild or captive, the favorite food of a full-grown 

 Rattler is small mammals; but what they feed 

 upon in a wild state when very young, remains to 

 be ascertained. From our six species of captives, 

 we have learned that Rattlers climb bushes with 

 almost as much ease as professional tree-climbers, 

 but in a wild state it seems fairly certain that they 

 rarely do so. 



The tail of the Rattlesnake is ornamented at 

 the end with a rattle consisting of a number of 

 joints of horny material developed out of the skin, 

 one section dovetailed into another. The exact 

 age of a Rattler is not indicated by the number 



ENGLISH NAME. 



LOCALITY. 



LATIN NAME. 



Dog-Faced Rattlesnake New Mexico Crotalus molossus. 



Timber Rattlesnake Eastern half of United States Crotalus horridus. 



Diamond Rattlesnake Florida and Gulf States Crotalus adamanteus. 



Texas Rattlesnake The Southwest Crotalus atrox. 



Prairie Rattlesnake The Plains Region Crotalus confluentus. 



Pacific Rattlesnake The- Pacific States Crotalus lucifer. 



Tiger Rattlesnake Extreme Southwest Crotalus tigris'. 



Horned Rattlesnake Extreme Southwest Crotalus cerastes. 



Green Rattlesnake Mexican Boundary Crotalus lepidu^. 



White Rattlesnake Southern and Lower California Crotalus mitchelli. 



Massasauga Nebraska to New York Sistrurus catenatus. 



Edwards' Massasauga The Southwest Sistrurus edwardsi. 



Ground Rattlesnake Atlantic States South Sistrurus miliarius. 



Among the Rattlesnake species are several 

 striking examples of color-development to suit 

 their surroundings, or what is known in well- 

 worn phrase as "protective coloration." The 

 Banded pr Timber Rattlesnake is a good imita- 

 tion of the color of dead leaves and damp earth. 

 The color-pattern of the Diamond Rattler is 

 made up of rich though quiet tones of brown and 

 yellow, dark and light, like the shadows of saw- 

 palmetto leaves falling upon yellow sand. The 

 Texas Rattler and the Horned Rattlesnake of 

 the Southwest are so pale and bleached one 

 instantly associates them with naked deserts 

 shimmering in fierce sunshine. 



In their habits, so far as known, the various 

 species are very much alike. They bring forth 



of joints in the rattle at the rate of one for each 

 year. On the contrary, under favorable cir- 

 cumstances about three joints will be developed 

 each year, until the snake reaches maturity. We 

 have now, in the Reptile House, Rattlesnakes 

 three years old which already have in their rattles 

 from seven to nine joints. 



The rattles are not shed when an old skin is 

 cast off, nor are they ever shed; but they are 

 frequently broken off, usually about three joints 

 each year after more than nine or ten joints have 

 been acquired. It is very seldom that more 

 than ten joints are found on a living snake. 



It is possible to lengthen a snake's rattles, 

 after they have been cut off, by joining on other 

 joints of the same size, up to the number desired. 



