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MISSOURI BOTANICAL GARDEN 



EXPLANATION OF PLATES. 



Plate 21. — Above, Opuntia Cardenche at right (1), 0. leptocaulis at left 

 (5): one of the others may be 0. KleiniaCj and the remaining two are 

 undcscribed species for which more data are needed. Below, O-Cardenc/t^; 

 cultivated specimens at beginning of the fourth year's growth from small 

 cuttings. 



Plate 22. — Opuntia arhuscula; introduced for comparison with Plate 23. 

 Above, the species as it grows naturally upon desert mesas near Tucson, 

 Ariz., in favorable situations. Below, a tree form as it grows in favorable 

 situations in deep canons in foothills of the mountains at an altitude of 

 about 4,000 feet. 



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Plate 23. — Above, Opuntia neoarbuscula in the center, 0. fusicaulis sit 

 the left. The former is in the beginning of the third years' growth from 

 small cuttings; the habit in nature and under cultivation is the same. 



Below, at the right, O. Chavena: a joint from a native specimen at Aguas 

 CaUcntes, Mexico. 



Plate 24. — Opuntia castillae. Above, a single plant, early in the fourth 

 yearns growth. Below, terminal joints. 



Plate 25. — Opuntia juliginosa. Above, a potted plant about three 

 years old. Below (marked by the basket), a native plant. The potted 



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plant, grown in a greenhouse at Washington, is no more like the parent 

 plant, in color, spine, or shape of joint, than 0. ftdgida is like 0. arborescens. 

 In open ground in California, the growth is normal. 



Plate 2G. — Opuntia Cochinera. Above, a typical native plant. Below, 

 a single joint and fruit. 



Plate 27.— Above, Opuntia discata: joints two months and one year 

 old. Below, 0. linguijormis: a mature cultivated plant. 



Plate 28. — Above, Opuntia macrocalyx: joints in bud. Below, 0. 

 microdasys: a cultivated plant, for comparison. 





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