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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 10 



0.9-1 X 0.9 mm ; ealycis tubus 0.05-0.1 mm altUs, lobis interioribus ca. 0.15 mm 

 longis remotis dentes exteriores tuberculatos aequantibus. Petala 0.7-0.75 X 0.7- 

 0.9 mm rotundata apice vix retusa basi ca. 0.15 mm unguiculata apicem versus 

 ad margines vix erosula glabra. Stamina isomorphica. Flores masculini : filamenta 

 1 mm longa ; antherarum thecae 0.5 X 0.35 mm obovatae apice truncatae et late 

 biporosae basim versus intus biseptatae, connectivo basi 0.1 mm prolongato 

 incrassato non lobulato ; ovarium abortivum non ovulatum, stylo 0.2 mm longo 

 incluso, stigmate punctiforme. Flores feminini : stamina abortiva, filamentis 0.8 

 mm longis, antherarum thecis 0.2 mm longis late biporosis, connectivo 0.15 mm 

 prolongato incrassato; stylus 1.5 X 0.3 mm ca. 1.2 mm e hypanthio eminens; 

 stigma eapitellatum 0.6 mm diam ; ovarium 3-loculare multispermum 2/3-inferum 

 glabrum apice in conum 0.2 mm altum elevatum ; semina 0.6 X 0.4 mm minutis- 

 sime tuberculata. 



Type. Inflorescence branches and hypanthium red-tinged, petals and stamens 

 white, locally frequent on dry side of middle falls of Rio Tirica below Summit 

 Camp, Chimanta Massif, Edo. Bolivar, Venezuela, alt. 1760 m, 1 Mar 1955, J. A. 

 Steyermark & J. J. Wurdack 1226 (holotype US 2342416). Paratypes. VEN- 

 EZUELA, Edo. Bolivar. Chimanta Massif: upper slopes of Apacara-tepui, alt. 

 1700-1850 m, Steyermark 75829; Torono-tepui, alt. 1895-1910 m, Steyermark & 

 Wurdack 1074; Agparaman-tepui, alt. 1880-1955 m, Steyermark & Wurdack 

 1129. 



Heterostyly has long been suspected in the minute-flowered Andean species of 

 Miconia Sect. Cremanium, but the inconspicuous (described) morphologic differ- 

 ences and lack of field observations have prevented acknowledgment of this 

 phenomenon. In M. dioica, there seems no doubt as to heterostyly and, judging 

 by the individual collections, dioecism ; the type collection is male, Steyermark 

 75829 is fruiting, and the other two paratypes are female flowering and fruiting. 

 M. manicata, from the Colombian Andes, has elliptic ciliolate leaf blades, manicate 

 branchlet nodes but with petioles simply inserted on the stems above the nodal 

 elevation, and somewhat larger flowers (petals 1.8 mm long and anthers 1.3 mm 

 long) ; the anthers are basally 4-celled as in the Guayana species. In Cogniaux' 

 monograph, M. dioica would key to M. tinifolia Naud. or M. pinetorum Naud., 

 both of which have larger flowers and lack elevated cauline nodes. Jamaican 

 material of M. rubcus (Sw.) Naud. (Nichols 108, Eggers 3622) shows a very 

 slight tendency towards nodal development and perhaps dioecism (or surely 

 heterostyly), but has oblong-elliptic serrulate leaf blades. In general habit, 

 M. dioim resembles M. sarmentosa Cogn. of French and Dutch Guiana. 



M. rupestris Ule was described as with 2-pored anthers; however all recent 

 material from Roraima, Ilu-tepui, the Chimanta Massif, and Auyan-tepui, agree- 

 ing with Ule's and Gleason's descriptions and the type photographs in minute 

 details (quadrangular stems, with caducous spinules), shows 4-pored anthers. 

 Apart from the purported 2-pored anthers, all of the features of M. rupestris 

 may be found within the many varieties of M. theaezans (Bonpl.) Cogn. (cf. var. 

 subtriplinervia Cogn., var. tetragona Cogn., var triplinervia Cogn.) ; accordingly, 

 I have referred nine collections from the four Venezuelan tepuis to M. theaezans. 

 As for material from Roraima and Ptari-tepui ascribed to M. tinifolia Naud., I 

 feel sure that it is at least subspecifically distinct from Andean collections, but 

 am deferring any adjustment until the Andean population is studied in detail. 

 A recent collection from Cerro Yutaje (Maguire & Maguire 35329), fruiting only, 

 seems also involved in the M. theaezans-M. tinifolia problem, having distinctly 



