238 



MEMOIRS OP THE NEW YORK BOTANICAL GARDEN 



| VOL. 10 



ing to the tops of these tepuis, as well as occurring elsewhere in areas of lower 

 altitude in sandy soil or along sandy rocks bordering streams, or near sea-level, 

 as near Georgetown, British Guiana, and along the Rio Para and Rio Icana in 

 Amazonian Brazil. They are further unique in being annuals, a type of plant 

 rarely encountered on the summits of the sandstone table mountains. 



3. Perama galioides (H.B.K.) Poir. Diet. Nat. 38 : 414. 1825. 



Mattuschkea galioides H.B.K. Nov. Gen. & Sp. PI. 2: 272. 1817; Spreng. Syst. Veg. ed. 

 16, 1: 418. 1825. 



Distribution. Southern Venezuela and British Guiana at elevations of 80- 

 1100 meters. 



Key to the Varieties and Forms of Perama galioides 



1. Corolla 6.5-8 mm long, the tube (including limb) 5-6.5 mm long, the limb externally 

 glabrous or minutely papillate-puberulent ; anthers 1.3-1.7 mm long. 



.3d. P. galioides var. longiflora. 



1. Corolla 4-6.5 mm long, the tube (including limb) 2.5-4.5 mm long, the limb externally 

 usually more or less pilosulous, rarely sparingly puberulent or glabrous; anthers 

 0.7-1.3 mm long. 



2. Stem glabrous to appressed-pubescent, the hairs in the lower portion not loosely 

 spreading. 



3. Leaves mainly ternate, rarely quaternate, 0.5-1.5 mm wide; heads 4.5-12 mm 

 long; seeds 0.6-0.7 mm long; stem commonly simple and monocephalous to 

 branched with 3 heads, rarely more, the upper internodes mostly elongated 

 with few whorls of short leaves at the upper nodes. 

 4. Leaves chiefly or always ternate. 3a. P. galioides var. galioides f. galioides. 



4. Leaves chiefly or always quaternate. 3b. P. galioides var. galioides f . quaternata. 

 3. Leaves mainly quaternate, 1.5-4 mm wide; heads 9-25 mm long; seeds 0.9-1 

 mm long; stem commonly much-branched with 3-10 heads, rarely monoceph- 

 alous, conspicuously f oliose at all the nodes with well-developed leaves at all ' 

 the nodes. 3c. P. galioides var. galioides f. macrocephala. 



2. Stem with some degree of spreading pubescence at least in lower portion or 

 at base. 



5. Calyx-divisions mainly loosely spreading, those from the lower and middle part 

 of the head divaricate, horizontal, or reflexed; flower-heads up to 8 mm wide, 

 11 mm long; nerves on lower surface of leaves somewhat prominent, but those 

 on either side of midrib less conspicuous or not prominently elevated; stems 

 and foliage, at least in dried state, dull or drab dark green, most of the hairs 

 white, gray, or colorless. 

 6T Hairs on calyx, stems, and, when present on leaves, buff to stramineous or 



ochroleucous at base. 3e. P. galioides var. hispida f . hispida. 



6. Hairs on calyx, stems, and leaves gray-white, the plant with a gray-hoary 



appearance. 3f. P. galioides var. hispida f. cinerea. 



5. Calyx-divisions strongly arched-ascending, erect-ascending, or arched-incurving 

 above; flower-heads up to 10 mm wide and 15 mm long; all the nerves on 

 lower surface of leaves equally prominent and conspicuously elevated; stems 

 and foliage, at least in dried state, dull olive green with usually yellow hairs. 



7. Pubescence of stems and both surfaces of leaves dense and conspicuous, that 



of stems 1-2 mm long, that of leaves 1.5-1.75 mm long; calyx-divisions 

 4-4.5 mm long; leaves'mainly divaricately spreading; leaves mainly quater- 

 nate, sometimes ternate. 3h. P. galioides var. densipila. 

 7. Pubescence of stems and both surfaces of leaves less conspicuous or more 

 sparsely distributed, that of stems 0.5-1 mm long, that of leaves 0.7-1.5 mm 

 long; calyx-divisions 2.5-4 mm long; leaves erect-ascending to spreading; 

 leaves mainly ternate. 3g. P. galioides var. intermedia. 



