RATHBUNIA. 



169 



name 



Drude, Veg. Krde 12 : 191 1), but was never published. 



Illustration: Kngler and Drude, Veg. Erde 12; pi. 5 b, as Pilocercus acranthi 

 Figure 237 is from a photograph taken by Dr. Rose at the type localit} 



figure 239^shows the flower, and figure 240 the fruit of the plants photographed. 



1914; 



RATHBUNIA 



909 



^ 



/ 



Rather slender cacti, simple or bushy, the stems and branches weak, erect or bent; ribs few, 4 

 to », prominent; spines subulate, those of the flowering areoles not differing from the others; flowers 

 diurnal, scarlet, solitary, usually at the upper areoles, narrowly tubular, the tube bearing distant 

 lohg scales and united with it except at the tip, elongated, at first straight, or in age somewhat 

 curved, the limb more or less oblique; perianth-segments short, spreading or rcflexed; filaments 

 exserted ; style slender, exserted beyond the tube ; stigma-lobes narrow; ovary with small scales bearing 

 short felt and sometimes spines in their axils; fruit capped by the withered flower, spiny or becoming 

 smooth, globular; seeds of the typical species black, compressed, minutely pitted, with a large basal 

 oblique hilum. 



Dr. Richard Rathbun (1852-1918),, Assistant Secretary of 



commemorates 



Sm 



manne 



Type species : Cereiis sonorensis Riinge. 



We 



natives of western Mexico. 



Key to Species. 



N 



Ribs 5 to 8; flowers 4 to to cm. long x, R. 



Ribs 4; flowers 12 cm. long - 2. if. 



1. Rathbunia alamosensis (Coulter) Britton and Rose, Contr. U. S. Nat. Herb. 12: 415. 



alamosensis 

 kerheri 



1909 



Cereus alamosensis Coulter, Contr. U. S. Nat. Herb. 3: 406. 1896. 

 Cereus sonorensis Riinge in Schumann, Monatsschr. Kakteenk. 11: 135. 

 Rathbunia sonorensis Britton and Rose, Contr. U. S. Nat. Herb. 12: 415, 

 Cereus pseudosonorensis Giirke, Monatsschr. Kakteenk. 20: 147. 19^0- 



1901. 

 1909 



Columnar, 2 to 3 meters high, at first erect but generally finally bent or curved, 8 cm. thick or 

 less, rooting at or near the tip and thus forming new plants; ribs 5 to 8, obtuse; radial spines about 

 II to 18, spreading, straight, whitish; centrals i to 4, much stouter than the radials, 3 to 5 cm. long, 

 porrect or ascending; flowers scarlet, 4 to 10 cm. long; scales on ovary small, acute or obtuse, with a 

 small tuft of felt and a few bristle-like spines in the axils, those on the flower-tube with a tuft of 

 felt and sometimes with a spine; tube-proper 1.5 cm. long; style 

 nearly white ; stigma-lobes 6, cream-colored ; ovary tuberculate ; fruit 

 red, globular, 3 to 4 cm. in diameter, naked or bearing scattered 

 clusters of 5 or 6 white acicular spines. 



Type locality: Near Alamos, Sonora, Mexico 



Distributi 



Southern Sonora, Sinaloa,' and Tepic, 



Mexico 



sometimes 8 meters 



diameter; its. flow 

 limb is apparently 

 In Mexico the plant is called cina. 



Hildmann (Monatsschr 



name 



1895), 



Gtirke, belongs here. Schumann at one time 



plant as Cereus stellatus, a very different 

 southern Mexico which we 



Schum 



from 



Fig. 241. 



have described elsewhere as ^'^" ^'^^• 



Lemaireocereus stellaius (see page 92, ante). 



Flower of Rathbunia ala- 

 mosensis. X0.7. 

 Flower of same, cut open. 



X0.7. 



Illustrations: Bliihende Kakteen 3:pl- 122; Monatsschr. Kakteenk. 11:135; Rep. 



Mo. B( 

 N achtr 



16: pi. 3, f. 5, all as Cereus sonorensis; Schumann, Gesamtb. 



Kakteen 



