146 REPTILES OF THE WORLD 



small gray lizards. In an instant the box was empty. 

 From beneath it, on the floor, darted a series of radiat- 

 ing streaks as the reptiles scurried in all directions ; some 

 continued their progress up the curtains, where they hid 

 among the folds at the top; afterward, the writer dis- 

 covered that half a dozen had jumped from the box 

 to his sleeve, thence to his back, where they dodged away 

 from his grasp like squirrels on a tree trunk. Placed in 

 a gauze cage with fine sand and rocks, in a sunny win- 

 dow, the lizards flourished. Unless the sun blazed upon 

 them they stubbornly refused the meal worms placed in 

 their cage. On dull, cloudy days all were stupid and 

 inactive. A considerable variation of color was noted; 

 on dull days the color was dark brown; in the sunshine 

 this gave way to ashen hues on which the dark transverse 

 bands were intensified. 



Genus Sceloporus; Spiny Swifts: For the thirty- 

 five species comprising this genus, the present popular 

 name is appropriate. The scales of the upper surface 

 are large, overlapping, usually coarsely keeled and 

 terminating in a sharp point ; on some of the species the 

 tips of the scales are really needle-like, curling slightly 

 outward and producing a generally bristling aspect. 

 Mexico and Central America are the headquarters of 

 these lively creatures, which scamper over the ground 

 or on logs with a speed that defies capture unless trick- 

 ery is employed; and the United States is well repre- 

 sented in species of the genus, particularly in the West- 

 ern States, where several of the larger species extend 

 northward from Mexico; there are a few species char- 

 acteristic of the country lying north of the boundary; 

 in the United States there is but one species extending 

 eastward as far as the Atlantic Coast. Few of these 

 swifts have any but dull brown or gray hues on the 



