Vol 35, pp. 179-189 October 17, 1922 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



TWO NEW SPECIES OF MORACEAE FROM SOUTH 



AMERICA. 



BY S. F. BLAKE. 



The two new species of the mulberry family here described 

 from the South American collections of H. M. Curran are both 

 good-sized forest trees of some commercial importance. Both 

 species were studied at the request of Professor S. J. Record, of 

 the Yale School of Forestry, who is engaged in a study of the 

 woods of this family. The species of Brosimopsis is of interest 

 as representing a second species of a hitherto monotypic genus. 



Brosimum columbianum Blake, sp. nov. 



Tree 30 m. high, 60 cm. in diameter; branchlets greenish white, glabrous, 

 obtusely angled, very leafy; petioles stout, sulcate above, sparsely pubes- 

 cent, 3 to 5 mm. long; leaf blades ovate or oblong-ovate, 4 to 9 cm. long, 

 2 to 3.3 cm. wide, shortly falcate-acuminate with obtuse apex, rounded or 

 cuneate-r iunded at base, entire, subcoriaceous, pale green, glabrous, nar- 

 rowly marginate, the costa flattish or slightly impressed above, prominent 

 beneath, the lateral veins 12 to 14 pairs, flattish or obscurely prominulous 

 above, prominent beneath, the secondaries finely reticulate but flyt on 

 both sides or even somewhat impressed beneath; receptacles solitary in the 

 axils, subglobose, 1.5 mm. thick in youth, 11 mm. thick when submature, at 

 first sessile, the pedicel becoming 1.5 mm. long at submaturity; receptacle 

 minutely puberulous and covered with peltate finely puberulous and cilio- 

 late bracts; pistillate flower solitary, the papillose style and stigmatic 

 branches together 5 mm. long, exserted from a very early period (when 

 receptacle is 1.5 mm. thick); staminate flowers not seen. 



Type in the U. S. National Herbarium, no. 1,068,154, collected in the 

 vicinity of Estrella, Cano Papayal, Lands of Loba, Bolivar, Colombia, 

 April or May, 1916, by H. M. Curran (no. 304). Duplicate in the herbar- 

 ium of Yale University. 



The native name of this timber tree is given by Mr. Curran as "guaya- 

 mero." The species is nearest Brosimum alicastrum Swartz, not definitely 

 known from South America, but is distinguished by its smaller leaves and 

 solitary always sessile young receptacles. It is probable that further 

 differences will be found when more complete specimens are collected. 

 35— Phoc. Biol. Soc. Wash., Vol. 35, 1922. (179) 



