ROBINSON: CONTRIBUTIONS FROM GRAY HERBARIUM. 257 
* * * Capitula plus minusve pedicellata in panicnla cymosa vel eorymbosa vel 
(in M. hirsutissima) obscure racemosa disposita. 
h— Caulis fulvo hirsutissimus; capitula in apicibus paniculae ramorum 
subracemosa. 
8. M. hirsutissima, DC., Prodr., v, 200 (1836).— On mountains, 
Velirla of Copey, alt. 1800-1900 m., April, 1898, Ad. Tonduz , no. 
12,208. A South American species. 
-t- -t- Caulis plus minusve pubescens, vel tomentosus, vel subglaber ■ capitula 
cymosa vel eorymbosa. 
++ Capitula 8-10 mm. longa. 
= Folia basi acuta vel acuminata. 
9. M. olivacea, Klatt, l. c., xxxi, pt. 1, 195 (1892). Foliis 
integerrimis. — In woods, Buenos Aires (Costa Rica), January, 1892, 
alt. 200-300 m., H. Pittier, no. 4933. This species is scarcely dis¬ 
tinct from M. Guaco , HBK. 
= — Folia basi cordata. 
10. M. cordifolia, Willd., Spec, pi., iii, 1746 (1804). Agua 
Caliente, H. Pittier , no. 137 ; in underbrush, Surubres near San 
Mateo, P. Biolley , no. 7025 ; Ujarras, Buenos Aires (Costa Rica), 
H. Pittier , no. 10,626 ; and at Navarro, Prov. Cartego, J. D. Smith , 
no. 4855. Widely distributed in the tropics of the New World. 
++ -4-1- Capitula minora, 5-6 mm. longa. 
11. M. scandens, Willd., 1. c., 1743 (1804). Foliis variabilibus 
sed semper tenuibus saepissime hastato-cordatis. — Costa Rica : PL 
Pittier , no. 3231 ; Ad. Tonduz , nos. 7067, 7264, 8589; P. Biolley , 
no. 7425. The commonest and most widely distributed species of 
the genus. 
3. *Notes on the Genus Mimosa in Mexico and Central 
America. 
Mimosa argillotropha, spec. nov. Frutex, ramis gracilibus 
obscure puberulis striatis atropurpureis aculeatissirais, aculeis parvis 
seriatim orientibus valde recurvatis peracutis 2 mm. longis; petiohs 
