1958] 



THE BOTANY OF THE GUAYANA HIGHLAND PART III 



141 



This is a form of the species with the veinlets of the leaflets more intricately 

 and more prominently raised. 



Pleonotoma dendrotricha Sandwith, sp. nov. 



P. variabili (Jacq.) Miers affinis, sed indumento denso pilorum parvorum 

 ramosorum stellatiformium secus ramulos folia inflorescentiasqne conspicuo, prae- 

 terea ovulis pro loculo 6-seriatis differt. P. tetraquetra (Cham.) Bur., Brasiliae 

 anstralis incola, qnae ovula pro loculo 6-seriata etiam praebet, indumento simili 

 sed e pilis multo majoribus constitute gaudet, praeterea foliis semper triternatis 

 lobis corollinis majoribus differt. 



Frutex ope cirrhorum scandens ; ramuli siccitate brunnei, pilis parvis furfur- 

 aeeis ramosis dendroideis stellatiformibus dense induti ; pseudostipulae hand 

 foliaceae, lineari-spathulatae, apice glanduliferae. Folia biternata, petiolo rhachi 

 pinnarum petiolulis siccitate brunneis indumento ramulorum subtomentosis ; 

 petiolus 1.5-2 cm longus; pinnae binae trifoliolatae ad 13 cm longae ; petioluli 

 laterales circiter 5 mm longi, terminales ad 1.8 cm longi ; foliola pinnarum 

 inaequalia, lateralia terminali minora, omnia chartacea, utrinque sed praesertim 

 subtus indumento dendroideo stellatiformi pubescentia, subtus quidem mollia 

 >iibvelutina, supra etiam lepidoto-punctata, costa nervisque supra subplanis 

 tenuissime prominulis subtus prominentibus, supra intricatissime rugosulo-sub- 

 Hsperula. Racemi breves, circiter ad 2 cm longi, nbique eodem indumento 

 subtomentosi ; pedicelli vix usque ad 1 cm longi; bracteae pleraeque circiter 1 

 mm longae, imae tantum longiores. Calyx tubuloso-campanulatus, 7-8.5 mm 

 'longus, apice ad 7 mm latus, dense minute pubescens vel demum fere glabrescens, 

 sub apice brevissime denticulato plus minusve incrassato-verrucosus atque glan- 

 dulas gerens. Corolla teste lectore alba, anguste campanulato-infundibularis, 



5- 6 cm longa, limbo siccitate ad 2.8 cm diametro ; tubus parte basali anguste 

 cylindrica 1.5-1.8 cm longa, apicem versus ad latitudinem 1.5-1.7 cm ampliatus. 

 extra nisi sub lobis glaber, intus zona lata pilorum sub insertione staminum 

 praeditus; lobi majores circiter 1.3 cm longi, 1.2 cm lati, omnes utrinque pilis 

 ramosis furfuraceis pubescentes praeterea glanduloso-lepidoti. Stamina circiter 1.5 

 cm supra tubi basin inserta, glabra, longiora circiter 2.4 cm breviora 1.7 cm longa, 

 thecis antherarum divaricatis 3.5 mm longis ; staminodium 4 mm longum. Discus 

 pulvinari-cupulatus, fere 1.5 mm altus. Ovarium ovoideo-oblongum, 1.5 mm 

 latum, crassum, plusminusve costatum sulcatumque, lepidotum ; stylus circiter 

 3 cm longus, conspicue sulcatus; ovula plurima (ultra 80), in quoque loculo 



6- seriata. Capsula lineari-oblonga, c. .45 cm longa, ad 1.7 cm lata, minute den- 

 droideo-pubescens atque lepidota, praeterea glandulis magnis patelliformibus im- 

 mersis notata ; semina omnino pallide brunnea, alis latis membranaceis, 1.2 cm 

 longa. 4—4.5 cm lata. 



Type : VENEZUELA : Territorio Amazonas, Rio Orinoco, 1-10 km below San 

 Fernando de Atabapo, 150 m. fl. May 11, 1954, J. Silverio Level 67 (holotype K, 

 isotype NY). ''Bejuco. Flores blancas." 



BRAZIL : Amazonas : Manaus, Carnpo Vieiralves, Adrianopolis, terra firme 

 arenoso, capoeira aberta, fr. Oct. 1955, leg. Chagas, Herb. Inst. Nac. Pesq. Ama- 

 zonia 2095 ; ibid., estrada antigua de S. Raimundo, terra firme arenoso, capoeira 

 fechada, fr. Oct. 1955, leg. Chagas, Herb. Inst. Nac. Pesq. Amazonia 2211. 



This interesting plant occupies a position between P. variabilis and P. tetra- 

 quetra, having the simply biternate 6-foliolate leaves and corolla of the former, 

 and the "dendroid" type of indumentum and 6-seriate ovules of the latter. It 

 is worth remarking here that P. clematis (H.B.K.) Miers,. which I have else- 



