Circular No. 66. U. S. Dept. of Agriculti 



Plate 2 



A.— Neomammillaria (Mammillaria) pyrrhocephala. Missouri Botanical Garden, 1910 B —Cory- 

 phantha {Mammillaria) cornifera. Missouri Botanical Garden, 1899. C —Echinopsis ca'lochlora, 

 showing the development of more spines in the grafted plant than in its parent. The grafted plant 

 is an offset from the other. Missouri Botanical Garden. 1907 



