202 THE CACTACEAE. 



Key to Species. 



Slender with linear lateral branches, their margins slightly toothed ; style and stamens about length of 



perianth-segments i . D. biformis 



Spreading with oblanceolate lateral branches, their margins crenate; style and stamens long-exserted. . 2. D. eichlamii 



1. Disocactus biformis Lindley in Edwards's Bot. Reg. 31: pi. 9. 1845. 



Cereus biformis Lindley in Edwards's Bot. Reg. 29: Misc. 51. 1S43. 

 Disisocactiis bifor?>iis Kunze, Bot. Zeit. 3: 533. 1845. 

 Phyllocactus biformis 'Laho-arel, Monogr. Cact. 418. 1853. 

 Epiphyllum biforme G. Don in Loudon, Encycl. PI. ed. 3. 1378. 1855. 



Plant 2 dm. long or longer; branches linear, 5 to 8 cm. long, i to 2 cm. broad, with serrate 

 margins; flower-bud elongated, cur\'ed upward, pointed; tube of the flower about i cm. long, the 

 segments 8 (rarely 9), magenta, about 3 cm. long, the outer 4 or 5 spreading or cur\^ed backward, 

 linear, the inner 3 or 4 broader and more erect; stamens 10 to 12, slightly exserted, borne in 2 series 

 at top of tube; style slender, purple; stigma-lobes 4, white; ovar}^ short-oblong, green, somewhat 

 tubercled, with a few areoles subtended by small ovate scales; fruit ovoid, 1.5 cm. long, turgid, 

 wine-colored. 



Type locality: Honduras. The species described from a garden specimen, introduced 

 into England in 1S39. 



Fig. 205. — Disocactus eichlamii. 



Distribution: Honduras and Guatemala. 



We have had this plant under obser\-ation for a number of years. It is rather a shy- 

 bloomer with us, although we get one or two flowers each spring ; the fiowers open in the 

 night or early morning and remain open all day ; they begin to wither the second morning. 

 The perianth-segments are more widely spreading in the morning than in the afternoon. 

 The flower is almost horizontal and the tube proper is about the length of the ovary. The 

 fruit matures very slo\vly. In 1920 we had a plant flower in April, but the fruit did not 

 mature until July 8. 



Illustrations: Forster, Handb. Cact. ed. 2. 876. f. 120; Riimpler, Sukkulenten f. 86, 

 as Disisocactus biformis; Bliihende Kakteen i: pi. 54; Curtis's Bot. Mag. loi: pi. 6156; 

 Diet. Gard. Nicholson 3: f. 135; Alonatsschr. Kakteenk. 9: 141; Watson, Cact. Cult. 50. 

 f. 12, as Phyllocactus bifonnis; Loudon, Encycl. PL ed. 3. 1379. f. 19403, as Epiphyllum 

 biforme; Edwards's Bot. Reg. 31: pi. 9; Palmer, Cult. Cact. 175. 



Plate XXXII, figure 2, shows a branch of a fruiting plant sent to Dr Rose by 

 Robert Lamb of Alanchester, England, in 191 2. Figure 203 shows the flower of the same 

 plant ; figure 204 is from a photograph of the same plant in flower. 



