PITTIER—PLANTS FROM COLOMBIA AND CENTRAL AMERICA. 101 
The following 9 species may be considered as definitely included in the genus: 
Brosimum alicastrum Swartz, Prodr. Veg. Ind. Occ. 12. 1788. West Indies and 
Mexico. 
Brosimum costaricanum Liebm. Dansk. Vid. Selsk. Afh. V. 2: 334. 1851. Costa 
Rica. 
Brosimum utile (H. B. K.) Pittier (below). Northern South America and 
Central America, from Venezuela to Nicaragua. 
Brosimum gaudichaudii Trécul, Ann. Sci. Nat. III. Bot. 8: 140. pl 6. f. 172-176. 
1846. Western Brazil. 
Brosimum glaucum Taub. Bot. Jahrb. Engler 12: Beibl. 27: 4. 1891. Brazil. 
Brosimum glaziovii Taub. op. cit. 12: Beibl. 27: 3. 1891. Brazil. 
Brosimum guianense Huber, Bol. Mus. Goeldi 6: 168. 1908, excl. syn. Ama- 
zonia. 
Brosimum pusillum Hassler, Bull. Herb. Boiss. II. 7: 362, 1907. Paraguay. 
Brosimum terrabanum Pittier, Contr. U. 8S. Nat. Herb. 18: 70. 1914. Costa 
Rica. 
All these species, according to their respective descriptions, possess the 
fundamental characters of the genus as originally established. With reference 
to the type, B. alicastrum, Swartz says* that the female flowers grow on dis- 
tinct trees, in other words, that the species is dicecious. This affirmation evi- 
dently rests on a faulty examination, the style and stigmas emerging from 
the scaly floral involucre sometimes before the anthers. This is illustrated in 
the plate by Trécul,? where receptacles at various stages of development are 
shown on the same branchiet. 
While the structure of the female flower is uniform all through the series, 
there is a fundamental difference in the structure of the stamen. In the type 
species, B. alicastrum Swartz, and in B. terrabanum Pittier, the anther consists 
of a single cell, in the shape of an orbicular cushion, placed horizontally at the 
apex of the filament; the dehiscence takes place around the outer edge, half 
the cell wall turning up as an inverted umbrella, the other half reflexed in 
the opposite direction. In the other known species the anthers are 2-celled, the 
cells being placed on both sides of the connective and splitting longitudinally. 
Thus the genus is naturally divided into two sections, Monotheca and Ditheca, 
which differ also as to their geographical distribution, since the species of 
the first type are found only in the West Indies and Middle America, while 
those of section Ditheca extend from Costa Rica southward. 
The cow tree or milk tree, Jong known as Brosimum galactodendron Don, 
will be fully treated below. 
The late Dr. Huber named his tree Brosimum guianense on the supposition 
that it was identical with Piratinera guianensis Aubl. and that Brosimum 
aubletii Poepp. & Endl., supposedly another name for the latter species, was not 
in accord with the nomenclatorial rules. We have already seen that the iden- 
tity of B. aubletii is very much in doubt. Concerning B. guianense, Dr. Huber 
wrote me a short time before his premature end that “Le réceptacle est un 
peu plus grand qu’un grain de plomb no. 8. Fleur femelle unique. Baie mure 
écailleuse, un peu plus grande qu’un petit pois.” Further, Dr. Huber sent at 
my request two specimens of this species, which are now deposited in the U. 8S. 
National Herbarium. They were collected by A. Ducke near Obidos, Amazonia 
(no. 9189) and in the alluvial forests of Rio Mapuera, Amazonia (no. 9072). 
While both answer the general description of Brosimum, the styles are not seen 
1P]. Ind. Oce. 1: 18. 1797. 
? Ann. Sci. Nat. III. Bot. 8: pl. 8. 1847. 
2 Bol, Mus. Goeldi 6: 168. 1909. 
