Vol. 34, pp. 43-46 March 31, 1921 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



NEW TREES AND SHRUBS FROM YUCATAN. 



BY S. F. BLAKE. 



The descriptions of the following new species of woody plants 

 from Yucatan, made by the writer several years ago, are pub- 

 Ushed here in order that the names may be available for use in 

 the work on "Trees and Shrubs of Mexico," by Mr. Paul C. 

 Standley of the U. S. National Herbarium, now in course of 

 publication. 



Acacia dolichostachya Blake, sp. nov. 



Shrub 5 meters high ; stem unarmed, glabrous, the older branchlets weakly- 

 armed with tiny indurate stipules, the younger minutely appressed-puberu- 

 lous; upper leaves (immature) bipinnate, 3 to 3.5 cm. long including petiole; 

 stipules 0.7 to 1 mm. long, subulate, straight, at length indurated or decidu- 

 ous; petiole 1.5 to 2.2 cm. long, sparsely puberulous, bearing below the mid- 

 dle a conspicuous oval or roundish gland 1 mm. long; rachis 1.3 to 1.5 cm. 

 long, bearing an apical gland; pinnae 5 pairs, 2 to 2.5 cm. long, puberulous 

 especially at the base of the leaflets; leaflets 24 to 29 pairs, linear-oblong, 

 3.5 mm. long, 0.5 mm. wide, or smaller, obtuse, truncate-rounded at base, 

 inequilateral, ciliolate, otherwise glabrous; spikes cylindric, numerous, axil- 

 lary, erect, 3 to 3.5 cm. long, about 6 mm. thick, the rachis strigillose; pe- 

 duncle 3 mm. long; flowers rather loosely spicate, 3 mm. long (including 

 the stamens); bracteoles curved, yellowish, 0.5 mm. long, persistent; calyx 

 turbinate, broadly truncate at base, strigillose, 0.6 mm. long, 5-lobed for 

 X its length, the lobes deltoid, obtusish; corolla (in dried specimen) pale 

 yellowish, 1.5 mm. long, strigillose, 5-lobed nearly to the middle, the lobes 

 ovate, acutish; stamens 30, with free filaments, surpassing the corolla, the 

 anther cells elliptic; ovary short-stiped, glabrous, 11 -ovulate; style curved. 



Type in the herbarium of the Field Columbian Museum, No. 446,819, 

 collected at Las Bocas, Silam, Yucatan, May, 1916, by G. F. Gaumer & 

 Sons (No. 23,329). 



This species belongs to the group Nudiflorae of the second subseries of the 

 Vulgares, as treated by Bentham. Its nearest ally is A. coulteri Benth., 

 from which it differs in the shorter spikes, smaller flowers with about half 

 6— Proc. Biol. Soc. Wash., Vol. 34, 1921. (43) 



