1958] 



THE BOTANY OF THE GUAYANA HIGHLAND PART III 



49 



A monotypic genus, known only from the Kaieteur Plateau near the head 

 of the falls. 



15. Windsorina Gleason, Bull. Torrey Club 50: 148. 1923. 

 Windsorina guianensis Gleason, Bull. Torrey Club 50: 148. 1923. 



Type : dense upland bush, Kangaruma-Potaro Landing, Potaro River, British 

 Guiana, June 1921, Gleason 272 (holotype NY). 



Besides the type, three other collections have been made, viz. : Amatuk Port- 

 age, Sandwith 1516; and Potaro Road, 106.5 mile, Maguire 32143; mile 107, 

 Maguire 32142. 



A monotypic genus represented by W. guianensis Gleason, apparently con- 

 fined to river level in the lower part of the Kaieteur Gorge. 



16. Maschalocephalus Gilg & Schumann, Engl. Jahrb. 28: 148. 1900. 

 Maschalocephalus dinklagei Gilg & Schumann, Bot. Jahrb. 28: 148. 1900. 



Type : Fishtown, Gran Bassa, Liberia, Oct 16, 1898, M. Dinklage 2088 (holo- 

 type B, isotypes G, K). 



A monotypic genus widely distributed in marshy savanna areas in African 

 Liberia. According to Baldwin 14 one collection is known from Sierra Leone, and 

 the species is expected to be found on the Ivory Coast. The African Maschalo- 

 cephalus is the only extra- American member of the Rapateaceae known. The 

 family otherwise is exclusively tropical American (see footnote, p. 21). 



GUTTIFERAE 



Clusia L. sect. Clusiastrum PI. & Tr. Ann. Sci. Nat. ser. IV. Bot. 13: 322. 1860; 

 emend Maguire. 



In his botanical report on the remarkable Guiana findings of the Schomburgk 

 brothers, Bentham (I.e.) described Clusia cuneata, which with C. crassifolia PI. 

 & Tr. became the basis for Planchon and Triana's Section Clusiastrum. In the 

 Flora brasiliensis, Engler 15 adapted Clusiastrum as a subsection of sect. Criuva, 

 including within it Clusia fragrans Gardn. and C. sessilis (Klotzsch) Engl. A 

 few years later Vesque 16 associated a fifth species, C. schomburgkii Vesque, with 

 the above four in Clusiastrum as a subsection of Criuva. And, finally, Engler 17 

 reinstated sect. Clusiastrum, including within it the five species recorded above 

 and Clusia plukenetii Urb. from islands of the Lesser Antilles, making in all six 

 species that had so far been accredited to the assemblage. I subscribe to the later 

 judgment of Engler, but would exclude certain species recognized by him. 



As a result of our recent field activities in Guayana, two additional species 

 of the group, C. stylosa Maguire and C. tabulamontana Maguire, have already 

 been described. 18 And now four further species are proposed herein. 



Clusiastrum, as recognized by both Vesque and Engler, does not represent a 

 natural community of species. Accordingly, the following realignment within 

 the sect. Clusiastrum is presented as a part of my continuing studies in the 

 Guttiferae. 



14 Am. Jour. Bot. 37: 402-405. 1950. 



15 Mart. Fl. Bras. 12: i 401. 1888. 



16 DC. Monogr. 8: 32-33. 1893. 



17 Nat. Pflanzenf. ed. 2. 21: 200. 1925. 

 !8Bull. Torrey Club 75: 419-420. 1948. 



