ROBINSON : CONTRIBUTIONS FROM GRAY HERBARIUM. 255 
5-lobatum abrupte dilatatis.— Palmares del General, valley of the 
Diquis, alt. 600 m., 9 January, 1898, II. Pittier , no. 12,030. 
The identification of this species has been obligingly verified by 
Dr. Otto Stapf at the Royal gardens of Kew. 
2. M. riparia, Greenman, spec. nov. “ Scandens, caule tereti 
striato glabro rubro-brunneo internodiis etiam ad 24 cm. longis; 
foliis oppositis petiolatis caudato-attenuatis apice acutis ultra mediam 
integerrimis basi saepe grosse dentibus paucis undulato-dentatis 
hastatis et sinu lato cordatis utrinque glabris; capitulis circa 
7 mm. altis basi 1-2-bracteolatis spicato-racemosis in paniculis 
pyramidatis dispositis, involucri squamulis anguste oblongis aliquid 
oblanceolatis acutiusculis vel obtusiusculis saepe plus minusve erosis 
glabris vel prope apicem inconspicue puberulis; pappi setis pallide 
rufo-brunneis, achaeniis glabris.— Thickets on the banks of the Rio 
Las Vueltas, Tucurrique, alt. 635 m., January, 1899, Ad. Tonduz , 
no. 13,163 (type in hb. Gr.). 
This species is most nearly related to M. hastata, Willd., and 
M. bogotensis , Bentli. From the-former it differs in having larger 
leaves, denser panicles, and longer heads ; from the latter in the 
more decidedly hastate leaves, longer and more oblong involucral 
scales, flowers fully a third longer, and finally in the brownish, less 
red pappus.” 
3. M. leiostacbya, Benth., PI. Hartw., 201 (1845); Hemsl.,. 
1. c., 103; Robinson & Greenman, l. c., 12 ; J. D. Smith, Enum. pi. 
Guat., v, 41.— Species foliis subcoriaceis reticulatis ovatis integerri¬ 
mis.— Suerre, Llanuras de Santa Clara, alt. 300 m., J. I). Smith, 
no. 6616. 
-t- -t- Capitula pedicellata. 
4. M. Houstonis, Willd., Spec, pi., iii, 1742 (1804); DC.,. 
Prodr., v, 190.— In woods, Shirores (Talamanca), alt. 100 m., Ad. 
Tonduz , no. 9316. 
* * Capitula in panicula thyrsoidea densa vel e glomerulis numerosis plus 
minusve globosis composita sessilia. 
— Achaeniuin corolla longius. 
5. M. Pittieri, spec. nov. Paniculis exceptis glaberrima, ramis 
teretibus curvatis; foliis ovatis integerrimis longe caudato-acumi- 
natis basi rotundatis subcoriaceis 7 cm. longis, 3 cm. latis subtus 
