358 safford: myrmecophilous acacias 



GROUP I. CERATOPHYSAE^ 



Pericarp indehiscent, inflated, thin, fragile, terminating in a sharp 

 spine-like beak. Nectar glands of the petiole and often of the lower 

 rachis, elongated, crater-like, opening by a linear aperture with a 

 raised (marginal) rim. 



Section 1. Spadicigerae Schenck 



Flowers in spadix-Iike cylindrical spikes, densely crowded on a fusiform 

 receptacle; peduncles thickened, bearing a 4-parted calyx-like involucel 

 near the base; minute interfloral pedicelled bracteoles with peltate, 

 acuminate laminae, in form often resembling the leaf of an Arum. 

 Midrib and upcurved lateral nerves of the leaflets usually conspicuous 

 beneath. 



1. Acacia spadicigera Schlecht. & Cham. Linnaea 5: 595. 1830; not 

 Acacia spadicigera Benth. Trans. Linn. Soc. London 30^: 514. 1875. 



Type in the Halle Herbarium, collected near La Laguna Verde, State 

 of Veracruz, Mexico, in March, 1820, by Schiede (no. 685). Photo- 

 graph and fragments of type in the U. S. National Herbarium. 



2. Acacia cubensis Schenck, Repert. Nov. Sp. Fedde 12: 360. 1913.- 

 Bot. Jahrb. Engler 50: 460. 1914. 



Type in the West Indian Herbarium of Krug and Urban, Berlin, 

 collected in northern Cuba, April 21, 1863, by C. Wright (no. 2402); 

 specimens collected by C. Wright, bearing the same number, in the 

 Grisebach Herbarium, Gottingen, and in the Gray Herbarium. 



3. Acacia Hemandezii sp. nov.^ Closely related to Acacia spadici- 

 gera Schlecht. & Cham, and A. nicoijensis Schenck, but readily distin- 

 guished from the former by the subsessile flower spikes, scabrous before 

 anthesis owing to the recurved points of the bracteoles; and from 

 the latter by the color of the spines and the fewer nectar glands. Large 

 spines of the vegetative branches resembling the horns of a bull, subterete, 

 widely spreading or incurved, sometimes fascicled and interlocking as in 

 A. spadicigera, but never polished, at first pale brown or olivaceous, in 

 age chestnut-colored or, when dead, grayish brown, the largest 8 to 10 cm. 

 long, 1.8 cm. broad at the base. Spikes borne on axillary flowering 

 branches like those of A. spadicigera, often subsessile, solitary or gemi- 

 nate, subtended by small leaves, these with subulate stipular spines; 

 peduncles puberulent, 2 to 5 mm. long, 3 mm. thick, with 4-toothed basal 

 involucel like that of A. spadicigera. Flowers before anthesis covered 

 by the laminae of the bracteoles, these lanceolate, very long-acuminate, 

 peltate, scabrous on the upper surface, the margin bearing a fringe of 

 minute straight hairs, the pedicels usually somewhat hirtellous with 

 fine white diaphanous hairs visible under the microscope; apices of the 



* Acaciae americanae cornigerae siliquis in spinam abeuntibus. See Hermann, 

 Paul. Paradisi Batavi Prodromus, p. 303. 1689. 



^ The Huitzmamaxalli (*• forked-thorn") of the Aztecs, described and figured in 

 1576 under the name Arbor cornigera by Francisco Herndndez. 



