318 PROCEEDINGS OF THE AMERICAN ACADEMY. 



flowering branches; flowers glabrous: fruit oblong, 4 cm. long, 8 mm. 

 broad, about 8-seeded, abruptly acuminate at each end, thin, lucid, hispid 

 on margin and valves with short spreading setcL\ — Benth. in Hook. 

 Jour. Bot. iv. 410, & Trans. Linn. Soc. xxx. 417. — Acatlau, 

 Andrieux (ace. to Benth.); Tomellin Canon, Oaxaca, altitude 775 m. 

 Pi' Ingle, no. 4635 (distrib. as M. disticlia); Acaponeta, Tepic, Hose, no. 

 1475 ; also in W. Mexico, Palmer, 1891-1892, without number. The 

 fruit of this species was unknown to Benth. The still sparing material 

 available has the fruit most often hispid and that form of pod is accord- 

 ingly assumed to be typical. A doubtful form with glabrous somewhat 

 more numerous and relatively narrower leaflets has been collected with- 

 out fruit in Oaxaca by L. C. Smith, no. 202, and Nelson, no. 2629. 

 Var. levior. Fruit nearly or quite free from hispidity : otherwise 

 indistinguishable from the plant here regarded as typical. — Collected 

 in W. Mexico, 1891-1892, by Dr. Edward Palmer, but without number 

 or more precise data. Types in herb. Gray and herb. U. S. Nat. Mus. 



++ -i-i- Pods tomentose, armed or unarmed ; segments subequilateral or longer than 



broad. 

 = Stems not glandular. 



a. Calyx subtruncate, very short, 0.8 mm. long, a quarter the lengtli of the 



corolla : spikes long. 



27. M. Palmeri, Rose. Large shrub, unarmed or with occasional 

 infra-stipular si^ines : pinn^ 9 to 15 pairs ; leaflets 7 to 10 pairs, elliptic- 

 oblong, not crowded, glabrous above, puberulent beneath : spikes 

 (including peduncles) 7 to 10 cm. long, numerous in showy terminal 

 leafless panicles ; flowers purplish, puberulent : young fruit linear-atten- 

 uate, tomentulose. — Contrib. U. S. Nat. Herb. i. 99. — Near Alamos, 

 Palmer, no. 628 ; collected in flower in September. 



28. M. fascicTilata, Benth. Shrub with stout angulate branches 

 and tawny or rusty-tomentose branchlets : spines short, broad-based, 

 dark red, mostly infra-axillary, commonly grouped by 2's or 3's : leaves 

 when well-developed 2 to 3 dm. in length; pinna3 11 to 20 pairs; leaflets 

 8 to 15 pairs, oblong, villous-tomentose upon both sides: spikes crowded 

 in a terminal raceme ; flowers silky-villous : pods narrow, attenuate, 

 ferrugineous-tomentose and hispid with numerous reddish brown rigid- 

 ulous setae. — Benth. in Hook. Lond. Jour. Bot. v. 88, & Trans. Linn. 

 Soc. xxx. 414; Wats. Proc. Am. Acad. xxii. 409. M. cinerea. Herb. 

 Pavon ace. to Benth. 1. c. Acacia fasciculata, Kunth, Mim. 75, 

 t. 23. — Originally collected near Guanajuato by Humboldt & Bon- 

 pland ; later by Karwinski without exact locality; on hillsides near 



