ROBINSON, — SPECIES OF MIMOSA. 811 
Tonduz, no. 1568; Honduras, J. D. Smith, no. 5215, Niederlein. In 
a considerable series of specimens it has been impossible to find any 
constant or satisfactory characters or combinations of characters to sepa- 
rate this species from the following forms here included as varieties. 
The differences of pubescence, which are striking in extremes, undergo 
the most gradual and complete intergradation and appear to be corre- 
lated with no other important distinctions. It is probable that all the 
forms here given cross freely when occurring in the same region. 
Var. strigosa (M. strigosa, Willd. 1. ¢.). Leaflets acutish, beset 
upon both surfaces with coarser strigose hairs. — Costa Rica, Oersted, 
8. 
Var. fioribunda (M. floribunda, Willd. 1. c. 1031). Leaflets acut- 
ish, glabrous above, covered below with appressed seta: pedunculate 
heads mostly collected in almost naked terminal racemes: corolla puber- 
ulent to tomentulose. — Jalisco, Palmer, no. 705 (coll, of 1886); Ori- 
zaba, Botter’, no. 569, Seaton, no. 141; Vera Cruz, Bourgeau, no. 
1541, ©. L. Smith, nos. 1142, 1716, 1719, Melson, nos. 72, 160; 
Puebla, Melson; Guatemala, Hayes, J. D. Smith, no. 3308. Captain 
Smith’s no. 5764 from Costa Rica, and Kerber’s nos. 119 and 353 from 
S. Mexico are good examples of transitions between JZ. albida and its var. 
Jloribunda. It is probable also that leaflets which are at first pubescent 
above are sometimes glabrate in age. 
Var. euryphylla. Scarcely armed : leaflets broad, obovate, rounded 
and merely mucronulate at the apex, glabrous and somewhat lucid 
above, appressed-villous beneath: corolla glabrous. — Collected by 
£. W. Nelson in the valley of Jiquipilas, Chiapas, altitude 675 to 850 
m., 16 to 18 August, 1895, no. 2927 (in herb. U. S. Nat. Mus.). 
Var. glabrior. Stem and branches nearly glabrous : leaflets acute 
or acutish, glabrous above, sparingly setose heneath : corolla glabrous. — 
M. Velloziana, Micheli in J. D. Smith, Pl. Guatem. &e. iv. 49, not Mart. 
“ — Coll. Heyde & Lua at Malpais, Dept. Santa Rosa, Guatemala, altitude 
1230 m.,, no. 4133 of J. D. Smith’s distrib. 
** Pinne 1 to several pairs; leaflets 3 to several pairs, smaller. 
+ Stems herbaceous (sometimes becoming slightly ligneous in M. pudica), hirsute 
with spreading often tawny hairs; pinne 1 or 2 (closely approximated) pairs. 
++ Leaflets ovate or obovate : fruit finely pubescent upon the valves. 
8. M. Skinneri, Benta. Low, much branched hirsute annual : 
leaves with 2 or 4 digitately arranged secondary rhachises; leaflets 
obovate, 3 to 8 pairs, crowded, obtuse, very sensitive, glabrous above, 
appressed tawny-villous below : infra-stipular spines stramineous, straight: 
