436 pittier: origin of chicle 



noticed that while most fallen trees are quickly reduced to mould, 

 the trunks of the balata-producing Mimusops, called also 

 nispero, would lie almost indefinitely, keeping in perfect condition. 

 From what has been explained so far, the following conclu- 

 sions can be drawn: 



1. The nisperos of Central and South America include several 

 species of Achras, Mimusops, and other genera of the Sapotaceae, 

 so that the name does not necessarily correspond to Achras 

 Zapota. 



2. The chicle of commerce is not extracted exclusively, if at 

 all, from the latter species, but mainly from other trees with the 

 same vernacular name. 



3. The famous door lintels of the ruins of Yucatan were not 

 made from the wood of Achras Zapota, but more likely from one 

 of the other nisperos in the region. 



4. The neotropical genus Achras is not monotypic. Besides 

 A. Zapota L., it includes up to the present, two more Central 

 American species, and others may come to light when the flora 

 of northern South America is thoroughly listed. 



5 . Considering the importance of the product, a further, careful 

 investigation of the facts, in loco, that is to say, in the valleys 

 of the Motagua and Rio Dulce, in Peten, Yucatan, and Tabasco, 

 is necessary, and should cover the months of April, May and 

 June, so that specimens in flower and fruit, as well as wood 

 samples, could be procured. 



Following are the descriptions of the two new species of Achras : 



Achras Chicle Pittier, sp. no v. 



A large, deciduous laticiferous tree, reaching a height of 25 m. and 

 over, with a basal diameter of 50 cm. and over, the trunk straight, 

 with a rugose or scaty bark, the crown high and elongate, the branchlets 

 thick and glabrous. 



Leaves alternate, petiolate, coriaceous, congested on the new growth 

 at the end of the branchlets; petioles subterete, narrowly canaliculate, 

 puberulent, 2.5 to 3 cm. long; leaf -blades obovate-elliptic, long-cuneate 

 at the base, subacute at the apex, 12 to 20 cm. long, 4 to 7 cm. broad, 

 glabrous, dark green and dull above, light green and almost glaucescent 

 beneath; costa impressed above, very prominent beneath, the primary 

 veins numerous, parallel, inconspicuous. Stipules not seen. 



Flowers very numerous, congested at the end of the branchlets, the 

 pedicels i .4 to 1.8 cm. long, puberulous; sepals 6 (3 + 3), those of the 



