98 CALIFORNIA ACADEMY OF SCIENCES. 



Owls are even more useful in keeping in check the undue 

 increase of these animals, especially the rattlesnake, as 

 their nocturnal habits bring them in frequent contact with 

 the "one-button," the hopeful descendent of the mature 

 C^'otalus. 



There are some other allies" still to be mentioned, who 

 give us no inconsiderable assistance in our attempts to get 

 rid of the rattlesnake. One of these is the king snake, 

 Ophiholus getulus. An incident which occurred in a drug 

 store in this city, where various living reptiles are kept in a 

 glass case, proves that the statement of the prowess of this 

 snake made b}^ old rancheros are founded on actual obser- 

 vation, and not as has been supposed, on vague tradition. 



A specimen of Ophiholus being one day added to the 

 happy family, attacked a rattlesnake immediately on its 

 entrance, and winding himself by an exceedingly rapid mo- 

 tion round the latter strangled him, but not before receiv- 

 ing a wound from the fangs of his foe from which he died 

 the next day. 



The confined space, preventing freedom of movement, in 

 which the conflict took place, was probably the cause of 

 this mishap. Similar statements have been made in regard 

 to PiUjopliis. As to Eutainia we may be certain that these 

 defenseless species do not disturb the rattlesnake, and as 

 their food is cliiefl}- frogs and small fish they do not inter- 

 fere with his food supply as Pityophis certainly does, by 

 feeding on ground squirrels, gophers, rats, mice, etc., and 

 Ophibolus still more, by climbing shrubs and devouring the 

 eggs and young of birds, a cheerful nocturnal custom of the 

 rattlesnake also. 



In relation to the amount of help given by these enemies 

 of the rattlesnake, they rank about as follows : 



First. — Owls, which feeding on the strictly nocturnal 

 " one-button," destroy a greater number of individuals, 

 needing more for food on account of their small size. 



