Ill 



exchisiveh' on herbarium material or on specimen> grown in 

 European botanical gardens. 



The Specip:s of Acacia and tiihiu Distribution. 



There seems to be some confusion in regard to the taxonomy 

 of the ant acacias. Recent botanists, following Bentham (1842) 

 distinguish three species, and I believe that the\- are right in so 

 doing, but 1 believe that the name of one of them will have to 

 be changed. Bentham cites the species as Acacia spadicigcra 

 Schlechtendal and Chamisso, A. sphœrocephala v'^chlechtendal 

 and Chamisso, and A. hindsii Bentham. I have seen all three 

 of these species growing, but imfortunately my knowledge of A. 

 sphœrocephala is unsatisfactor}', because this species was not in 

 flower during my visit to Central America, and as I was unaware 

 of the pecuharity of its nectaries till after I had consulted the 

 literature and the specimens in the Gray Herbarium, I probably 

 overlooked it repeatedly in the field on account of its close re- 

 semblance to A. spadicigcra. I did, however, see an isolated bush 

 of sphœrocephala at Las Sabanas, near Panama Cit}', as I have 

 since learned from examining some leaves and thorns preserved 

 in alcohol with the ants. The species known as spadicigcra and 

 hindsii I observed in great numbers, often growing side by side, 

 especially at Escuintla and Patuhil in Guatemala. Both species 

 bore fruit, and in a few localities spadicigcra had begun to blossom. 

 The most striking characters of the three species are the following : 



A. spadicigera Schlechtendal and Chamisso is a shrub 

 growing to a height of 10 to 20 feet, often with rather few and 

 diffuse branches. The stipular thorns are large, swollen, gradually 

 tapering towards their tips, and cylindrical or but very slightly 

 compressed at the base. The leaves have a large crateriform 

 nectary at the base of the petiole, and a series of similar but 

 smaller nectaries, each opposite the insertions of a pair of pinnie. 

 The flower-spike is elongate, clavate-cylindrical. with a thick 

 l)ulp\' peduncle bearing the small, dinsi' llowrrs. The Iruit 

 is thick, spindle-shaped, bright red and leathery when mature, 

 with a long, slender beak, and contains a butter-like, sweetish, 

 edible pulp, in which the black seeds are embedded. 



.■1. hindsii Pxiitliam gr(«w> t(j a larger si/.i- than the prectding. 



