134 CALIFORNIA DESERT TRAILS 



sprouting horns, give the sidewinder an extra devil- 

 ish air, and his small size makes him the more dan- 

 gerous, because less easily seen and heard. His track, 

 however, is unmistakable, owing to his peculiar 

 mode of travel, which seems to be by looping him- 

 self along in spiral reaches, so that his trail is not 

 a continuous line, but a series of short, diagonal 

 strokes, about nine inches apart. For some reason 

 he enjoys wheelruts, and always takes advantage 

 of them : but as he moves mainly by night he is not 

 often seen by the traveller on the road. 



It is a strange fact, of which I have been assured 

 by more than one person who has put it to the proof, 

 that a sidewinder kept exposed to direct summer 

 sun will not live longer than a few minutes.^ The 

 explanation must be that the thin skin gives no pro- 

 tection to the cold reptilian blood. Certain it is that 

 the sidewinder is rarely seen in the open by day, but 

 is almost always found coiled in the shade, usually 

 about the roots of brush. It would be a praiseworthy 

 act of Sol, one for which I could forgive him much, 

 if he would one day turn on for a short time such a 



^ I have recently had an opportunity to test this on a sidewinder 

 that I brought in to camp for photographic purposes. It was a full- 

 grown specimen, and was not in the least injured in process of cap- 

 turing. I turned it into an enclosure of boxes, in the open sunshine. 

 It was as vicious and full of life as ever at first, but after three or four 

 minutes became languid, then ceased to move. Soon the head drew 

 back and the mouth opened, as in the attitude of striking. In ten 

 minutes it was dead. The month was September and the temperature 

 at the time io6° in the shade. With a midsummer temperature, ten 

 or fifteen degrees higher, no doubt, the time would have been much 

 shorter, perhaps two or three minutes only, as reported to me by 

 another experimenter. It is certainly remarkable that a desert crea- 

 ture should be so constituted. 



