1957] 



THE BOTANY OF THE GUAYANA HIGHLAND—PART II 



377 



ceous except for a few marginal members which may represent merely inner 

 reduced phyllaries, and the corolla more "advanced" with short, thin 5-nerved 

 tube and stiff, erect lobes. In Chimantaea the corolla lobes are densely barbate, 

 the achenes more often pubescent, and the nectar-gland at the summit of the 

 achene external to the style base is prominent and deeply 5-lobed (in other 

 members of the Guayana gochnatinias cylindric or prismatic). In habit, members 

 of the genus are conspicuously specialized, having become subsucculent, 

 depressed and little branched, or completely unbranched and in aspect more 

 like a bromeliad or espeletia than any of its congeners. Indeed, Chimantaea 

 seems in this respect well on the way to the development of the herbaceous 

 habit. The genus, except for C. cinerea (on nearby Auyan-tepuf) is restricted 

 to the Chimanta iMassif. 



Quelchia. 



Shrubby with lateral compound inflorescence; has achieved the ultimate in 

 capitulum reduction. All heads are uniflorous. The genus is geographically 

 restricted to the eastern part of the Guayana Highland. 



Subtribe Mutisinae. 



Guayana members of the Mutisinae with bilabiate (or ligulate) corollas 

 follow much the same pattern or organization and phyletic differentiation as 

 that observed for the Gochnatinae. There is one central large "primitive" more 

 or less polymorphic group, Gongylolepis, out of which, similarly, has come a 

 series of small but distinct satellite genera. 



Gongylolepis. 



The basic genus, composed of eleven species and three subspecific taxa. 

 It, like its gochnatinioid analogue, is arboreous, has large massive many- 

 flowered, many-bracted terminal solitary heads, large flowers with complex 

 venation, ample pinninerved leaves, and is geographically widespread throughout 

 Guayana. It is believed to have given rise to at least three genera, each of 

 which has 3 or fewer species. All are shrubby, have small few-flowered heads, 

 simpler "advanced" small flowers, and are each geographically restricted. 



Duidaea. 



Has developed three distinct species, and is perhaps closest to Gongylolepis 

 in general character. Its leaves are 1-nerved and linear, flowers have a simpli- 

 fied or "advanced" vascularization; and the pollen shows a prominent departure 

 in form and ornamentation. 



The two genera, Neblinaea and Achnopogon are monotypic, and each is geo- 

 graphically restricted to a single sedimentary massif. Both have compound, 

 laterally disposed inflorescences and small heads with five or fewer flowers, 

 the corollas of simple vasculature. Beyond these common features they differ 

 greatly. 



Neblinaea 



A well-branched shrub with small gongylolepioid leaves, glabrous phyllaries 

 and corollas, and anthers sagittate with adjacent tails connate. 



Achnopogon 



A suffrutescent shrub with a short thick primary axis bearing short-shoots 

 terminated by dense rosettes of leaves, and provided with one or several virgate 

 branches. Its phyllaries are strongly bearded, corollas puberulent, and anthers 

 simply caudate but not sagittate, a feature peculiar to this among all the Gua- 

 yana genera. 



