2l6 THE CACTACEAE. 



PUBLISHED SPECIES, KNOWN TO US ONLY FROM DESCRIPTION. 

 Cereus estrellensis Weber (Monatsschr. Kakteenk. 15: 167. 1905) is, according 

 to C. Werckle, similar to Cereus nycticallus but weaker and more spiny. The stems are 

 6-angled; the flowers are small, rosy to salmon-colored, and nocturnal. It is of Costa Rican 

 origin, but is known to us only from this brief characterization and may belong to our genus 

 Weberocereus. 



7. WERCKLEOCEREUS Britton and Rose, Contr. U. S. Nat. Herb. 12: 432. 1909. 



Epiphytic, climbing cacti, the 3-angled branches emitting aerial roots, their areoles bearing 

 short bristles or very weak spines and a tuft of felt; flowers short-funnelform, the tube rather stout; 

 ovary and flower-tube bearing many areoles, each with several nearly black, acieular spines and a 

 tuft of short black felt, subtended by minute scales; outer perianth-segments lanceolate, acutish, 

 narrow; inner perianth-segments broader; stamens many; style about as long as the longer stamens, 

 with several linear stigma-lobes; berry globose, its areoles spiny. 



Two species are known, 1 in Costa Rica and 1 in Guatemala; both are in cultivation. 

 The genus is dedicated to C. Werckle, a Costa Rican collector. 

 Type species: Cereus tonduzii Weber. 

 In habit the plants resemble species of Hylocereus, but the flowers are very different. 



Key to Species. 



Flowers 8 cm. long or less; stem-areoles at most bristly . . .1. W- tonduzii 



Flowers 10 cm. long or more; stem-areoles with weak but definite spines 2. W. glaber 



1. Werckleocereus tonduzii (Weber) Britton and Rose, Contr. U. S. Nat. Herb. 12: 432. 1909. 



Cereus tonduzii Weber, Bull. Mus. Hist. Nat. Paris 8: 459. 1902. 

 Stems rather stout, bushy-branched, the joints 3-angled, rarely 4-angled, deep green, not at 

 all glaucous, climbing by aerial roots; margins of ribs nearly straight; areoles small, felted, without 

 spines, but sometimes with weak bristles; flowers 8 cm. long or less, areoles of the ovary and tube 

 bearing clusters of dark spines and short black wool; outer perianth-segments brownish, oblong, 

 1 to 2 cm. long; inner perianth-segments oblong, creamy white, 2.5 cm. long; stamens exserted; 

 style longer than the stamens; berry globose, citron -yellow, its apex umbilicate, its flesh white. 



Type locality: Copey, near Santa Maria de Dota, Costa Rica. 



Distribution: Costa Rica. 



In greenhouse cultivation some plants are remarkably floriferous and very conspicu- 

 ous when in bloom. 



Plate xxxix, figure 3, shows part of a plant which flowered in the New York Botanical 

 Garden, March 30, 1908. Figure 296 is from a photograph of a plant in the same collection. 



2. Werckleocereus glaber (Eichlam) Britton and Rose, Addisonia 2 : 13. 1917. 



Cereus glaber Eichlam, Monatsschr. Kakteenk. 20: 150. 1910. 

 Stems slender, 3-angled, about 2 cm. broad, pale green and slightly glaucous, climbing by aerial 

 roots; margins somewhat knobby, the areole borne on the upper part of the knob, small, 3 to 4 cm. 

 apart; spines 2 to 4, short, 1 to 3 mm. long, acieular, but with swollen bases; flower 10 cm. long or 

 more, the ovary and tube bearing clusters of yellow to brown acieular spines ; inner perianth-segments 

 white, oblanceolate, acute, somewhat serrate; style pale yellow, weak, resting on the under side of 

 the flower- tube; stigma-lobes white; fruit not known. 



Type locality: Western coast of Guatemala. 



Distribution: Guatemala. 



In habit this species much resembles Wilmattea minutiflora, also from Guatemala, 

 but its flower characters are quite different. 



Illustration: Addisonia 2: pi. 47. 



Plate xxxix, figure 4, is from a specimen obtained by Dr. Rose from Guatemala, 

 which flowered in the New York Botanical Garden, April 14, 1915. 



