2950 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Leaves alternate, petiolate, thick and coriaceous, crowded at the ends of the 
Shoots. Petioles 2 to 8 cm. long, rather thick, roundish, obscurely canaliculate 
or flattened above. Leaf blades 8 to 14 cm. long, 4.5 to 6.5 cm. broad, obovate 
or oblong-elliptic, short-acute at the base, rounded-obtuse at the apex, smooth 
and almost glossy above, at first golden brown or ferruginous beneath, becoming 
brownish green. Costa impressed above, very salient beneath; primary veins 
slender, parallel, numerous (about 38 on each side of costa), scarcely distinct 
on the upper face of leaf, slightly salient beneath and anastomosed along the 
margin. Stipules narrowly lanceolate, about 5 mm. long, caducous. 
Flowers fasciculate in the axils of the leaves, 3 to 12 in each cluster. Pedicels 
about 3 cm. long (equal to, or longer than, the petioles), more or less. brown- 
ish-pubescent and thickening toward the end. Sepals 6, biseriate, about 6 mm. 
long, 3 to 3.5 mm. broad, ovate, obtuse or more or less attenuate at the tip, coria- 
ceous, the 3 exterior ones downy-pubescent, the interior ones grayish-pubescent 
outside, all glabrous inside. Corolla caducous, about 6.5 mm. long, white, mi- 
nutely pubescent outside, glabrous inside, spreading; tube 1.5 mm. long; lobes 
18, the 6 interior ones 4 mm. long, narrowly lanceolate with rounded tip and in- 
flexed margin, the 12 exterior ones about 5 mm. long, lanceolate, acute, broad at 
the base (1.5 to 2 mm.), a few entire, but the most bifid. Staminodes and 
Stamens connate at the base, the former lanceolate, subulate, about 2 mm. long, 
more or less minutely denticulate on the margin. Stamens 6, about 3 mm. long; 
filaments subulate; anthers ovate, short-apiculate, extrorse. Pistil entirely 
glabrous, 6.5 mm. long; ovary 9-celled. 
Type in the U. S. National Herbarium, no. 679446, collected on hills back of 
Puerto Obaldia, San Blas Coast, Panama, flowers, August 31, 1911, by H. Pittier 
(no. 4318). 
OTHER COLLECTIONS ! 
PANAMA: Forests of the hills around Gattin, Canal Zone, leaves only, Feb- 
i ruary, 1911, Pittier 2699. Hills of Sperdf, near Puerto Obaldfa, San 
& Blas Coast, young fruits, September 5, 1911, Pittier 4384. 
Of no. 4318, the type of the species, no fruits were collected; no. 4384 is a 
specimen with a fruit in its first stage of development and consequently too 
immature to furnish good characters. With the leaves of no, 2699, two more 
advanced berries were obtained, but the whiteness of the seeds shows that they 
were not quite mature. The fruits are ovoid, perfectly smooth, mucronate, 
about 3 cm. long and 2.5 cm. in diameter; 8 of the 9 cells are empty, and in 
each fruit the remaining cell contains 1 seed. This is large and flattened, with 
the hilum near the lower extremity. Although still immature, these seeds seem 
to have reached their full size, and measure 12.5 mm. in length, 5.5 mm. in 
breadth on the hilum side, and 6 mm. in thickness from the hilum to the carina. 
With the Costa Rican Mimusops spectabilis Pittier, this new species belongs 
to section Ternaria of the subgenus Eumimusops or Manilkaria. Through its 
subentire, subulate staminodes, it is related to the former, and also to M. longi- 
folia A, DC., but differs widely by other floral characters, as for instance the 
entire lobes and lobules of the corolla, the scarcely denticulate staminodes, and 
the multiflorous axial clusters of the inflorescence. 
Mimusops darienensis has great economic importance as the source of the 
Panama “balata” or “ gutta-percha,” and the wood is also very valuable. 
From an ecological standpoint the tree, which is very abundant in the hilly hin- 
terland of the Caribbean coast, is to be considered as a characteristic element of 
the rain forests of the eastern part of the Isthmus. Its presence on the southern 
or Pacific slope has been reported by natives, but as yet lacks confirmation. 
