1953] 



BOTANY OF THE GUAYANA HIGHLAND 



155 



2. Subsect. Paniculata Maguire, subsect. nov. Capitulis plurimeris; inflores- 

 centiis paniculatis vel umbellato-corymbosis; involucris 2.5-3°5 cm. latis. Typus, 

 Gongylolepis paniculata Maguire. 



1. Section Parvifolia Maguire, sect. nov. Foliis ferme minus 12 cm. longis 4 cm. 

 latis coriaceis, nervis primariis fere ad margines extendentibus valde reticulatis. 



Subsect. Erioclada Maguire, subsect. nov. Capitulo solitario; foliis cuneatis 

 vel obovatis. Typus, Gongylolepis erioclada Blake. 



Subsect. Benthamiana Maguire, subsect. nov. Capitulis plurimeris; foliis 

 spathulatis. Typus, Gongylolepis benthamiana P,ob. Schomburgk. 



Key to the Species of Gongylolepis 



1. Leaves ample (lO-)12-20(-27) cm. long, (3~)4-9 cm. wide, chartaceous, 

 primary veins extending little beyond the middle, then anastomosing 

 and with the secondary veins reticulate, veins on upper surface merely 

 prominulous, blades sessile or the petiole broadly winged (sect. Am- 

 plifolia). 



2. Inflorescence monocephalous (subsect. Bracteata). 



3. Peduncle with several conspicuous foliar bracts subtending the 



solitary head. 1. Gongylolepis bracteata. 



3. Peduncle ebracteate or with 1-3 inconspicuous or reduced bracts, 



and these not closely subtending the solitary head. 2. Gongylolepis pedunculata. 

 2. Inflorescence polycephalous (subsect. Paniculata). 

 3. Stems and immature leaves wholly glabrous. 



4. Involucre at maturity 42-45 mm. long (ex descr.). 3. Gongylolepis colombiana. 

 4. Involucre at maturity 30-35 mm. long. 4. Gongylolepis paniculata. 



3. Stems and immature leaves densly villous-pilose. 5. Gongylolepis yapacana. 



1. Leaves smaller 3-12(-15) cm. long, 1— 4(-6) cm. broad, decidedly petiolate 

 (in G. benthamiana the petioles are winged and less obvious), coria- 

 ceous, the primary veins extending nearly to the margins before anas- 

 tomosing, veins on upper surface prominent, strongly reticulate (sect. 

 Parvifolia). 



2. Inflorescence monocephalous (subsect. Erioclada). 

 3. Stems and leaves strongly appressed-pilose. 



4. Heads ca. 2 cm. long, sessile; involucral bracts coriaceous gla- 

 brous within, corolla glabrous; leaves prominently pinna-nerved 

 and reticulate on the upper surface. 6. Gongylolepis erioclada. 



4. Heads 2.5—3.0 cm. long with peduncles 8-15 mm. long; involucral 

 bracts chartaceous, puberulent within, corolla puberulent; leaves 

 inconspicuously nerved and reticulate above. 7. Gongylolepis paruana. 



3. Stems and leaves glabrous; heads ca. 3.5 cm. long, involucral bracts 

 coriaceous glabrous within; leaves cuneate obovate, 4-9 cm. long 

 2-6 cm. broad. 8. Gongylolepis glaberrima. 



2. Inflorescence polycephalous, leaves spathulate (subsect. Benthamiana). 

 5. Stems wholly glabrous; leaves sessile or the petiole broadly winged, 

 primary veins ca. 12 pairs conspicuous and recurved upwards, sec- 

 ondary veins prominently reticulate; achenes glabrous; known only 

 from the Gran Sabana. 9. Gongylolepis benthamiana. 1 * 



34 Another species, not recorded above, is Gongylolepis maroana Dadillo, 3ol. Soc. 

 Ven. Ci. Nat. 8: 237 (1943), the type of which is Williams 14394 Maroa, Rio Guainia, 

 Venezuela. This element apparently is conspecific with Stifftia martiana Baker in Mart. 

 Fl. Bras. 6 3 : 351 (18 84), collected by Martius in "alto Amazonas, in horrida solitudine 

 montis Araracoara, 500 pedes supra fluvium Japura." We understand that other authors 

 are elsewhere making the necessary nomenclatural adjustment to accommodate the transfer 

 and synonymy. 



The species seems to be most closely related to G. benthamiana Rob. Schomb. (see 

 above), and may be distinguished most readily from the Schomburgk species by the dis- 

 tinct (1-2 cm.) petiolation of the leaves, the smaller (2 cm. long) heads, and the purplish- 

 brown rather than pale straw-colored pappus. 



