SAFFORD : MYRMECOPHILOUS ACACIAS . 367 



teoles. Peduncles long, straight, slender, puberulent or hirtellous, borne 

 upon axillary flowering branches, solitary or clustered. Large stipular 

 spines straight or nearly so, widespreading, at first puberulent, except at 

 the smooth glossy reddish pomt, sometimes glabrate in age, but the 

 surface dull and never polished. 



22. Acacia Standleyi sp. nov. Flower spikes club-shaped, at anthesis, 

 thicker at the apex than at the base, 18 to 22 mm. long, 7 to 8 mm. thick, 

 pubescent before anthesis; peduncles in clusters of 2 to 5, the longest 

 27 mm. long at anthesis, minutely pubescent below the involucel, the 

 latter 4-toothed, pubescent outside, situated at or above the middle of 

 the peduncle; axis of spike slightly thicker than the peduncle. Flowers 

 with pale yellowish brown or buff, broadly tubular, obtusely lobed calyx 

 and tan-colored, acutely 6-lobed corolla, the latter exceeding the calyx 

 by one-half its length; stamens very numerous, yellow; style filiform. 

 Large spines pubescent at first, with glabrous reddish points, at length 

 dull gray or blackish, 3 to 3.5 cm. long, 6 to 8 mm. broad at the base, very 

 widely divergent, the pair separated by a thickened ridge (the persistent 

 base of the petiole) adiiate to the branch. Vegetative leaves with about 

 25 pairs of pinnae; main rachis pubescent above, about 10 cm. long, with 



1 to 3 conspicuous glands at the base and a gland just below each of the 2 

 or 3 terminal pairs of pinnae, these glands usually with a smooth, light 

 browTi, annular margin; piimae about 2.5 cm. long, those of a pair some- 

 times not quite opposite; rachis of pinnae pubescent above; leaflets about 

 30 pairs, approximate, relatively thick and coriaceous, scarcely showing 

 the venation even under the microscope, oblong-linear, 3.2 mm. long, 

 0.8 mm. broad, unequal at the base, rounded at the apex, sometimes 

 mucronulate or tipped with an apical body, the margin at first bearing a 

 frmge of minute hairs, at length glabrate. Leaves of the axillary flower- 

 mg branches with 4 to 8 pairs of pinnae composed of 12 to 16 pairs of 

 leaflets, these 2 mm. long, 0.6 mm. broad, when young fringed with 

 hairs, many of them tipped with apical bodies; main rachis bearing a 

 conspicuous annular nectar gland at the base of each pair of pinnae and 

 usually one on the petiole, just below the lowest of these; stipular spines 

 subulate, 4 mm. long. 



Type in the U. S. National Herbarium, no. 637251, collected in the 

 vicinity of Acaponeta, Territory of Tepic, western Mexico, April 11, 

 1910, by Rose, Standley, and Russell (no. 14374). 



23. Acacia hirtipes sp. nov. Flower spikes oblong or cylindrical, 11 to 

 15 mm. long, 6 mm. thick, covered before anthesis by the tomentulose 

 laminae of the bracteoles; peduncles densely hirtellous, in clusters of 



2 or 3, 14 to 20 mm. long; mvolucel 4-toothed, hirtellous, situated above 

 the middle of the peduncle; axis scarcely thicker than the peduncle. 

 Flowers with reddish brown or tan-colored calyx resembling that of 

 A. Standleyi but narrower at the base and pubescent about the shallowly 

 lobed margui; corolla dark purple or blackish, exceeding the calyx by 

 one-half or three-fourths its length,, pubescent with whitish hairs around 

 the 5- or 6-lobed margin; filaments reddish browTi; anthers pale tan- 



