CACTACEAE. 237 



1. DATISCA L. DuRANGO Root. 

 Characters of the family. 



1. D. glomerata (Presl) B. & W. Stems erect, 1-2 m. high, 

 simple or sparingly branched; leaves ovate or lanceolate in outline, 

 acuminate, about 15 cm. long, the floral shorter; flowers 4-7 in each 

 axil of the long leafy raceme; petals minute or wanting; the fertile 

 flowers perfect; anthers subsessile, 4 mm, long, yellow; styles ex- 

 ceeding the ovary; capsule oblong-ovate, 6-8 mm. long, slightly 

 narrowed toward the truncate triangular 3-toothed summit. 



Frequent along the streams in all our mountains, mostly in the 

 upper portions of the chaparral belt. 



Family 70. CACTACEAE. Cactus Family. 

 Fleshy plants with flattened, terete, rigid or tuber- 

 culed, continuous or jointed stems, leafless or with small 

 leaves, generally spiny, the spines developed from cush- 

 ions of minute bristles (areolae). Flowers mostly soli- 

 tary, sessile, terminal or lateral, perfect, regular and 

 showy. Calyx-tube adnate to the ovary, its limb many- 

 lobed or with distinct sepals. Petals nu merous in several 

 rows, mostly distinct. Stamens numerous, inserted on 

 the throat of the calyx, with filiform filaments and small 

 anthers. Ovary 1-celled, with numerous anatropous 

 ovules borne on several parietal placentae. Style ter- 

 minal, elongated; stigmas numerous. Fruit a berry, 

 mostly fleshy. Seeds smooth or tubercled, the testa 

 usually crustaceous or bony; endosperm scanty or 

 copious. 



Spines never barbed; flower-bearing areolae dis- 

 tinct from those bearing the spines. 1. Bergerocactus. 



Spines minutely barbed; flowers from the same 



areolae as the spines. 2. Opuntia. 



1. BERGEROCACTUS Brit. & Rose. 



Stems cylindric, with the spine-bearing areolae 

 on vertical ribs. Flowers from the older or fully de- 

 veloped parts of the plant bursting through the epidermis 

 just above the bunches of spines, usually about as long 

 as broad, sometimes elongated. Scales of the ovary 

 distinct, with woolly axils and acicular spines. Fruit 



