124 



THE CACTACEAE. 



As understood by us this species varies greatly in the relative thickness of its branches, 

 in armament, and in the size of its flowers. Its geographical range is, in our conception, 

 greater than that of most cacti. 



Cereus baxaniensis ramosus (Salm-Dyck in Walpers, Repert. Bot. 2:277. l8 43) is 

 published only as a synonym. Cereus arcuatus Zuccarini (Monatsschr. Kakteenk. 14: 55. 

 1904) from its description is of this relationship. It was originally collected at Totolapa, 

 Mexico, by Zuccarini. 



Cereus bajanensis Werckle (Monatsschr. Kakteenk. 15: 166. 1905) was never described 

 but belongs here. Cereus quadrangularis Haworth (Syn. PI. Succ. 181. 1812; C.trigonus 

 quadrangularis Pfeiffer, Enum. Cact. 118. 1837; Cactus quadrangularis Loudon, Encycl. 

 PI. 412. f. 6876. 1829) may belong here, but Pfeiffer referred it with a question to Cereus 

 caripensis De Candolle (Prodr. 3:467. 1828; Cactus caripensis Humboldt, Bonpland, and 

 Kunth, Nov. Gen. et Sp. 6: 66. 1823), but this species was referred by Schumann to the 

 genus Rhipsalis. 



Fig. 184. — Acanthocere 



f Charles Deering at Buena Vista. Florida, May 19 18. 



Cereus undulatus Pfeiffer (Enum. Cact. 107. 1837), based on a specimen in the Dresden 

 Garden, is usually referred to Cereus acutangulus, but was not described by Pfeiffer at the 

 place here cited. 



A specimen in the Berlin Garden also was called Cereus undulatus by D. Dietrich (Syn. 

 PI 3: 104. 1843) and described, but should be referred elsewhere. It is of quite different 

 relationship, being very slender, dull green, 10-ribbed. The flowers are large, 12.5 cm. in 

 diameter, white. Its native habitat is unknown. 



Illustrations: Cact. Journ. 1: 125; Cact. Mex. Bound, pi. 60, f. 5, 6, all these as Cereus 

 variabilis; Monatsschr. Kakteenk. 13: 158; Rev. Hort. Beige 40: after p. 184; Tribune 

 Hort. 4: pi- i4°> as Cereus baxaniensis. 



Plate xvi, figure 1, shows a flower and part of a joint of a plant sent from the Berlin 

 Botanic Garden to the New York Botanical Garden. Figure 182 is from a photograph 



