STAXDLEY TREES AND SHRUBS OF MEXICO. 905 



of the sour one, called tajud by the Cochimi, and this lasts through Septem- 

 ber and October or, if the season is favorable, even into November. The 

 branches of this plant also are ridged, spiny, and without leaves, but the 

 ridges are more ordinary and the spines larger, denser, and stouter. The 

 branches are straight and parallel like those of the tamniid or sweet pitahayo ; 

 but from the trunk they take different directions, without any order or 

 symmetry and, stretching over the ground, they throw out roots and form 

 new plants; interlacing with each other, there result thickets which are 

 unpleasant to look at and impenetrable by animals. The plant differs from 

 the first kind also in the places in which it grows; for that fruits well 

 anywhere in the mountains or on the plains, provided it is dry, while this is 

 found only on the plains near the coast, and if plants are found occasionally 

 in the mountains they are always sterile." 



14. NYCTOCERETJS Britt. & Rose, Contr. U. S. Nat. Herb. 12: 423. 1909. 



Erect or clambering, slender, sparingly branched cacti, with cylindric ribbed 

 stems and branches ; ribs numerous, low ; areoles each bearing a tuft of short 

 white wool and small radiating acicular bristles or weak spines; flowers 

 large, white, nocturnal ; ovary bearing small scales, short or long wool, and 

 tufts of weak spines or bristles ; perianth funnelform, gradually expand- 

 ing above, bearing scales and tufts of weak bristles below the middle, above 

 the middle bearing narrowly lanceolate scales distant from each other and 

 grading into the blunt outer perianth segments; inner perianth segments 

 widely spreading, obtuse or acutish ; stamens numerous, shorter than the 

 perianth ; style about as long as the stamens ; fruit fleshy, scaly, spiny 

 or bristly; seeds large, black. 



Three other species are known, natives of Central America. 



Flower tube longer than the limb 1. N. serpentinus. 



Flower tube not longer than the limb 2. N. oaxacensis. 



1. Nyctocereus serpentinus (Lag. & Rodr.) Britt. & Rose, Contr. U. S. Nat. 

 Herb. 12: 423. 1909. 



Cactus serpentinus Lag. & Rodr. Anal. Cienc. Nat. Madrid 4: 261. 1801. 



Cactus amhiguus Bonpl. Descr. PI. Rar. 90. 1813. 



Cereus serpentinus DC. Prodr. 3: 467. 1828. 



Cereus anibiguus DC. Prodr. 3: 467. 1828. 



Cereus splendens Salm-Dyck, Cact. Hort. Dyck. 1S49. 214. 1850. 



Mexico, probably native near the eastern coast. 



Stems growing in a cluster or clump, at first erect, then clambering through 

 bushes or over walls or, when without support, creeping or hanging, often 



3 meters long, 2 to 5 cm. in diameter ; ribs 10 to 13, low and rounded ; areoles 

 close together, felted and with acicular or bristle-like spines; spines about 12, 

 white to brownish, the tips usually darker, the longest about 3 cm. long ; 

 flowers borne at the upper areoles, sometimes terminal, 15 to 19 cm. long, 

 the limb 8 cm. broad ; areoles on ovary and flower tul)e bristly ; inner perianth 

 segments white, spatulate, obtuse; fruit red, covered vrith deciduous spines, 



4 cm. long; seeds black, 5 mm. long. " Junco espinoso " (Jalisco, Oaxaca) ; 

 "gigante" (Durango) ; " reina de la noclie." 



This species is commonly cultivated for ornament in Mexico and is often 

 found half wild about houses and in hedges. It is supposed to be a native, 

 but has not been found really wild in recent years. 



