414 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
DESCRIPTIONS OF GENERA WITH LISTS OF SPECIES. 
1. CEREUS Mill. Gard. Dict. ed. 8. 1768. 
CEREUS subgenus PreraNnrHocereus Berger. 
Night-flowering cacti with columnar upright, branching, ribbed, fluted or angled 
stems and branches, the areoles bearing several spines; flowers funnelform, elon- 
gated, the corolla falling away from a ring a little above the ovary after expanding; 
ovary bearing a few small scales but no spines nor wool; corolla tube nearly cylin- 
dric, somewhat expanded above, bearing a few similar scales, or naked; outer 
perianth segments obtuse, the inner acute, the petaloid ones bright white; stamens 
numerous, differing much in length; style included, the linear stigmas numerous; 
fruit fleshy, naked, sunken at the top, the persistent style recurved; seeds numer- 
ous, black, the testa punctate. 
Type species Cereus peruvianus Mill. 
Cereus hexagonus (L.) Mill. Gard. Dict. ed. 8 no. 1. 1768. 
Cactus hexagonus L. Sp. Pl. 466. 1753. 
Cactus peruvianus L. Sp. Pl. 467. 1753. 
Cereus peruvianus Mill. Gard. Dict. ed. 8. no, 4. 1768. 
Cereus alacriportanus Mart.; Pfeiff. Enum. Cact. 87, 1837. 
TYPE LocALITy: Jamaica; there, however, not indigenous but introduced from 
Peru. 
DisrripuTion: South America; widely planted and naturalized in the West Indies 
and Central America. 
InLusrrations: Vell. Fl. Flum. pl. 78. 19; Pfeiff. Abb. u. Beschr. pl. 5; DC. Mem. 
Mus. Paris 17: pl. 77. 
Clearly of South American origin, 
Cereus jamacaru DC. Prod. 3: 467. 1828. PLATE LXI. 
“Type Locauity: In Brazil. 
Disrrisution: South America. Planted in the West Indies; perhaps naturalized 
on some islands. 
ILiustRATION: Pison, Hist. Nat. Bras. 100. f. 7; Bot. Mag. 95: pl. 5775, as C. lividus. 
EXPLANATION OF PLATE LXI.—From a photograph taken by M. A. Howe, at Santurce, Porto Rico. 
Cereus nudiflorus Fngelm. Anal. Acad. Ciene. Habana 6: 98. 1869. 
Type Locauity: Beaches near Havana and Guantanamo, Cuba. 
Distrisution: Cuba. 
Tuiusrrations: Contr. Nat. Herb. 12: pis. 49-51; Journ. N. Y. Bot. Gard. 10: pi. 28. 
Erroneously referred by Schumann to Cereus lepidotus Salm-Dyck, a native of north- 
ern South America, planted in the West Indies. 
2. RATHBUNIA gen. nov. 
Plants not large, the stem and branches often weak; spines stout, those of the 
flowering areoles not differing from the others; flowers diurnal, single from the 
areoles, very narrow and elongated, trumpet-shaped, somewhat curved, oblique at 
mouth, scarlet; petals very short, spreading, reflexed, or rolled back; stamens 
inserted near the middle of the tube, exserted; fruit globular; seeds black, com- 
pressed, minutely pitted, with a large basal oblique hilum, 
Named for Dr. Richard Rathbun, Assistant Secretary of the Smithsonian Institu- 
tion in charge of the U. 8. National Museum, a well-known authority on marine 
invertebrates. 
Type species Cereus sonorensis Runge. 
