Plate 13 



Devil's head cactus (Echinocactus texensis). The cluster of 

 bright scarlet fruits is even more attractive than the pink blossoms. 

 Its central spines are so strong and tough that they frequently 

 cripple horses and cattle temporarily and readily pierce the sides of 

 the foot of a strong shoe or boot. (Photograph by Mrs. B. Macken- 

 sen). 



Devil's pin-cushion (Mamillaria heyderi). This species is fairly 

 common but is rarely seen, unless a close search is made. It usually 

 grows in the shelter of a bush or in the protection of a clump of 

 prickly pear. Plants found in the southern sandy area invariably 

 have less radial spines than those of the hilly regions of the north, 

 which would lead one to believe that two species are found here. 



