The Tuna. 151 



2H inches in diameter, smooth, with over sixty areoUe of fine spines 

 distributed over its surface, a fourtli bordering the deep brownish 

 umbilicus wliicli is an incli across. Spines usually few, short and 

 M^eak; whitish, often entirely absent. 



oprxTiA TTXA — Linn. 



'A native of Mexico and Columbia. Tall, broad-spreading plant, 

 large, rather long (10 to 20 cm.) ovate or elliptical stems, the edges 

 curving, with pointed green leaves seven mm. long. Covered with 

 bunches of spines growing close together at base of stems, and wider 

 apart at top, like gray felt in color, the upper spines brownish- 

 yellow, underneath four to six stiff, bodkin-like, light j^eliow spines 

 of uttequal length (9 to 21 cm.) Petals the shape of rose leaves, 

 mucronate; stamens yellow; stigma five-lobed; green.'— Forster's 

 Cacteen. 



The tuna which I take to be this species bears a very juicy, 

 sweet, delicious fruit, yellowish-green when mature, nearly three 

 inches long and two inches in diameter, with fewer seeds (about 

 150;. The greenish-white, firm pulp is very cool and refreshing, 

 from which the seeds do not readily separate as in the tuna Colorado. 

 The slightly glaucous e»>idermis of the fruit is similarly armed with 

 an equal number of areola? of fine, short spines, very disagreeable, 

 but easily disposed of by an expert — though dangerous to a novice if 

 he should stand to windward while brushing them off the fruit, when 

 they are liable to blow into the eyes with disastrous results. The 

 average Mexican or Indian learns to handle these fruits with utter 

 indifference to the spines. 



The spines are abundant and rather formidable in appearance 

 on this beautiful plant, but are really one of the most useful charac- 

 teristics of the plant, making it very useful for hedges and fences. 



OPUNTIA TUXA MAXSE. 



The color of the fruit of this tuna outside is of a deep orchra- 

 ceous-buff", slightly glaucous, irregularly mottled and blotched with 

 crimson, giving it a bloodshot appearance; inside the outer coating 

 is of the same coloring, but the pulp inclosing the seeds is of a light 

 greenish-yellow. 



This is the most abundant of tlie three forms of tunas natural- 

 ized at the 8an Diego Mission, and like the others is credited with a 

 Mexican nativity. The fruit is nearly globose, with a yellowish 

 umbilicus, pitted in the center, an inch in diameter and smaller 

 proportionally than in tuna or tuna Colorado. Seeds more numerous 

 (about 250). Areolae and spines on fruit and stems differ but slightly 

 if any from O. tuna, from which the plants may not be readily dis- 

 tinguished except when in fruit. C. R. Orcutt. 



