1958] 



THE BOTANY OF THE GUAYANA HIGHLAND PART III 



19 



Distribution : open sandy flats and savannas, coastal Suriname, British 

 Guiana, and Rio Paragua (Orinoco drainage), Venezuela. 



Specimens examined: SURINAME: perennial herb, frequent open sandy area subject to 

 frequent inundation, west side of railroad, Zanderij, June 3, 1944, Maguire 4" Stahel 33667 

 (type of A. psammophila Maguire). BRITISH GUIANA: common on savanna, "fl. white," 

 Karakara, Demerara River, Feb 1910, C. W. Anderson F. D. No. 510 (K, NY). VENEZUELA: 

 Cardona 823 (holotype VEN, isotypes NY, F). 



17. Abolboda acaulis Maguire, Bull. Torrey Club 75: 191. 1948. 



Type : locally frequent, tufted perennial herb 2-3 cm high, rootstocks fleshy, 

 flowers 1 or 2, pale blue ; in white sand from conglomerate and sandstone, Kaie- 

 teur Plateau, British Guiana, April 30, 1944, Maguire & Fanshawe 23096. 



Distribution : plants of savannas and open stream-sides at higher altitudes, on 

 wet sand overlying Roraima sediments. 



Specimens examined: BRITISH GUIANA: Kaieteur Plateau: Maguire 4' Fanshawe 

 23096 (holotype NY, isotype F, NY, US, K) ; Feb 15, 1955, Maguire, Bagshaw 4 Maguire 

 40700; 40701; savanna above Chi Chi Landing, Mazaruni River, Feb 10, 1955, Maguire, Bag- 

 shaw 4 Maguire 40669; 40669- A; scrub savanna, Kamarang Station, Maguire 4" Fanshawe 

 32609; Imbaimadai Savannas, Maguire 4 Fanshawe 32169; Holi-tipu, Maguire 4" Famhawe 

 32516; Ayanganna Savannas, Maguire, Bagshaw and Maguire 40618. VENEZUELA: Boli- 

 var: Kavanayen, Maguire 33730; 33749; San Rafael, Maguire 33179; Chimanta, Bteyermark 

 75784; SteyermarTc 4" Wurdaclc 457 ; Guaiquinima, Maguire 32820. Amazonas: Cerro Sipapo, 

 Maguire 4~ Politi 27659; 27700; 27778 ; 27923; 28691; Cerro Huachamacari, Maguire, Cowan 

 4- Wurdaclc 30154; 30720; Cerro Guanay, Maguire, Phelps, Hitchcock # Budowslci 31703; 

 31773- A; Cerro Yutaje, Maguire 4 Maguire 35214; 35249. 



RAPATEACEAE 



-The taxonomic history of the family began in 1775 with the description by 

 Aublet (I.e.) of Rapatea paludosa. By 1873, in the notable monograph of K6r- 

 nicke (I.e.), 19 species held in seven genera were presented. In 1930, Pilger, in 

 the Natiirlichen Pflanzenfamilien, listed nine genera and 25 species. Now, chiefly 

 as a result of contemporary exploration in South American Guayana, 16 genera 9 

 and some 80 species are known, an increase during the past two and a half 

 decades of seven genera and 55 species. 



Perhaps no other family of flowering plants can be considered more charac- 

 teristic of the phytogeographic province of Guayana than the Rapateaceae. Its 

 members occupy a most prominent place on the ' ' cumbres ' ' of the tabular moun- 

 tains and the open upland plains of the Gran Sabana of the Roraima sandstone 

 regions, and are ornamentally conspicuous on the historically and in some re- 

 spects ecologically related low altitude natural savannas of the Upper Rio Orinoco 

 and Rio Negro drainages. 



The center of distribution and the greatest concentration of genera and spe- 

 cies lie within the periphery of Guayana. Of the 16 genera now known, 10 

 with a specific population of some 41 species are entirely confined to this region. 

 Of the remaining six genera, only two, the monotypic African Maschalocephalus 

 and the bitypic trans-Andean Epiphyton are wholly extra-Guayanan. Within 

 the four genera Rapatea, Saxofridericia, Cephalostemon, and Spathanthus, with 

 a total of 31 species, 13 are wholly extra-Guayanan, 15 wholly Guayanan, and 



9 The two largest genera, Rapatea and Stegolepis, with some 20 species now known for 

 each, are not treated in this review. The opportunity of further study in the field interrupts 

 this writing and dictates the postponement of even a preliminary presentation of these two 

 most complex genera of the family, until return is made from our imminently approaching 

 expedition to Guayana in Amazonian Venezuela. 



