278 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [Vol. 8, No. 4 



I 



lated to the latter species with M. brevense as an intermediate relative. M. mach- 

 aerioides, however, appears to be much more intimately related to M. gracile and 

 probably had its origin independently of the other more remotely related species. 

 It is most easily recognized by the angular-auriculate upper side of the leaflet 

 base and by the strongly emarginate leaflet apices. 



4. Macrolobium brevense Ducke, Arch. Jard. Bot. Rio de Janeiro 4: 50. 1925. Fig- 

 ure 3. 



Large tree 20-30 m. tall, the branchlets pilose and puberulous. Stipules 4.5 

 mm. long, caducous, subulate, acuminate, ciliolate. Petioles 2-4 mm. long, pilose 

 or pilosulose. Leaf blades elliptic-oblong to oblong-lanceolate, 18-27-jugate, the 

 pairs of leaflets 3-6 mm. apart; rachis 5.5-11.5 cm. long, the wings ciliolate, 

 sparsely pilosulose on the upper surface, glabrous beneath, the axis uncinate- 

 puberulous on the upper surface, sparingly pilosulose or glabrous beneath. Leaf- 

 lets (1.5-)5-20 mm. long, 1-7 mm. wide, the upper ones minute, oblong, the base 

 inequilateral, the upper side obtuse to cordate, the lower side subobtuse, the apex 

 rotund, emarginate, minutely apiculate; upper surface glabrous except for arcuate 

 or uncinate hairs on the costa, beneath glabrous or the costa with very few hairs; 

 costa strongly salient, the venules obscure on the upper surface, subprominulous 

 beneath. Inflorescences 2-5.5 cm. long, the axis densely short-pilosulose, the 

 peduncle 2-3 mm. long; bracts 2 mm. long, 1 mm. wide, caducous, triangular, 

 acute, glabrous within, pilosulose externally; pedicels 1.5-3 mm. long; bracteoles 

 5-5.5 mm. long, 2.5-3.5 mm. wide, oblong or oblong-obovate, subappressed flexu- 

 ose-pilosulose and pilose on the outer surface, villose within. Hypanthium 1.5 mm. 

 long, sessile, glabrous or sometimes with few hairs. Sepals five, 1.5-3 mm. long, 

 1-1.5 mm. wide, triangular-lanceolate, ciliate apically. Petal blade 4-5 mm. long, 

 3-4.5 mm. wide, orbicular, the claw 4.5-7.5 mm. long, glabrous within, villosulose 

 externally. Filaments about 12 mm. long, villosulose in the lower part. Stigma 

 simple or subcapitellate. Style about 15 mm. long, pilosulose basally. Ovary 2- 

 2.5 mm. long, 1-1.5 mm. wide, oblong to oblong-oblanceolate, 3-4-ovulate, mar- 

 ginally pilose, the lateral surfaces glabrous, the gynophore 2.5 mm. long, pilose, 

 inserted at the base of the hypanthium. Fruit (submature) 13.5 cm. long, 4-4.5 cm. 

 wide, oblong, glabrous, the carpophores about 10 mm. long, glabrous. 



LECTOTYPE: A. Ducke (H.J.B.R. No.) 16946 (flowering portion), "Breves, 

 aestuario amazonico, civ. Para, silva primaria circa campinam arenosam," July 

 1923 (deposited U, isolectotype US). The fruiting portion of this collection was 

 collected in the same locality but on a much earlier date, December 1922. Both 

 the flowering and fruiting material is considered to be representative of this 

 species. 



The^selection of a lectotype was necessary here because Ducke, in his origi- 

 nal description, cited only a single collection, which under most circumstances 

 would be considered as the holotype. However, it really included two collections, 

 and the International Rules provide that in such a situation a lectotype must be 

 chosen. 



Additional Specimens: BRAZIL: Esperan^a ad ostium flum.. Javary, Amazonas, Jan. 

 1942, Ducke 899 (F, IAN, MO, NY, US); Breves, civ. Para, Aug. 1926, Ducke (H.J.B.R. 

 No.) 16946- A (F-frag., G, NY, P, RB, U, US). The latter collection has previously borne 

 the number "16946" which is the number of the lectotype collection. The number has been 

 emended to read as shown above to avoid future confusion. 



The geographic distribution of this species is rather surprising but entirely 

 understandable in a region so poorly known floristically. Its type locality is 

 Breves (from which locality the specific epithet is drawn) in the mouth of the 

 Amazon River and is known elsewhere only from Esperanca, Amazonas in the 



