30 HOUGH'S AMERICAN WOODS. 



Fruit & pulpy umbilicate berry, smooth or furnished with spines and containing 

 numerous seeds, with or without albumen, buried in the pulp. 



A large order of few genera, but many species, of plants of very peculiar aspect, 

 confined quite exclusively to the American continent, natives of dry arid regions 

 and most abundant in or near the tropics. 



GENUS OPUNTIA, TOUNREFORT, 



Leaves small, subulate, on the young branches and early deciduous. Flowers 

 yellow, red or purple, sessile and solitary, on the joints of the previous year, 

 springing from the ariolse which produce the spines, with short cup-shaped 

 tube; calyx-tube not produced beyond the ovary, lobes numerous; petals spread- 

 ing or half erect; stamens shorter than the petals; ovary bearing bristles in the 

 axils of the deciduous sepals. Fruit succulent and often edible, pear-shaped or 

 barrel-shaped berries, truncate, with wide umbilicose apex, bearing small and 

 easily detachable spines in the ariolse and containing large white compressed 

 seeds having embryo coiled around the albumen; cotyledons large and foliacious. 



Fleshy, articulated and much-branched plants, low and prostrate or erect and 

 shrub or tree-like with stems quite terete at base and branches flattened or 

 terete and bearing in ariolse numerous minutely barbed spines and bristles. 

 A large genus of one hundred and fifty or more species, natives of America, but 

 some have become widely naturalized in the old world. Opuntia is from the 

 name of a Greek town, 'Oirovs, near which some cactus-like plants were men- 

 tioned by Pliny as growing. 



184. OPUNTIA TUNA, MILL. 



MISSION CACTUS. INDIAN FIG-. PRICKLY PEAR. 



Ger., Indische Feige ; Fr., F'tyue '/ ' Indien ; Sp., Tunal. 



SPECIFIC CHARACTERS: Joints of the branches flat and obovate to oblong with 

 rather distant fascicles of stout yellow spreading unequal minutely barbed 

 spines. Fruit rich carmine within, 2-4 in. long and furnished with minute 

 prickles, edible. 



(Tuna is the Spanish name of the fruit of the Indian Fig.) 



An erect or inclining Cactus, sometimes 15 ft. (4.50 m.) in height, 

 with branches formed by the wide Hat joints, armed with strong yel- 

 low spines, sometimes 2 in. in length, and short cylindrical but still- 

 jointed trunk, sometimes 12 or 18 in. (0.40 m.) or more in diameter. 

 In thickets of the Cactus the trunk is longer, sinuous and partially 

 procumbent. 



HABITAT. The native home of the Opuntia Tuna is South 

 America and the West Indies. It has been extensively introduced, 

 however, into southern Europe and other warm regions. It wa> 

 early planted about the old missions of southern California, and has 

 there become naturalized, springing occasionally from seed and often 

 from detached joints which have been dumped in waste places and there 

 take root. 



PHYSICAL PUOPKKTIKS. Wood of very loose open structure, really 

 a framework, with intervals filled with a thick viscid, colorless fluid. 



