252 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Tetrapteris paniculata. BEJUCO DE PARALEJO. 
A vine-like biennial shrub; growsin various parts of theisland. (Stahl, 2: 151.) 
Tetrazygia elaeagnoides. CENIZO. 
Family Melastomaceae; a much-branched shrub 4 to 5 meters high, frequent- 
ing limestone hills. Bello calls this *‘ verdeseco.”’ (Stahl, 4: 3.) 
Tetrazygia stahlii. CENIZO. 
A shrub 3 meters high, with cinnamon bark, grows cn rocks at an elevation of 
1,500 feet. (Stahl, 4: 113.) 
Thalia geniculata. 
Family Marantaceae: has very large. abruptly ovate, closely veined leaves and 
peculiar zigzag flower stalks: known from Anasco. (Sintenis.) 
Theobroma cacao. Cacao. 
The cultivation of cacao is becoming one of the major industries of the Tropics, 
and as such is reasonably safe from the commercial side, although market prices 
will undoubtedly be subject to fluctuation, as with all staple articles. A great 
objection to the extensive cultivation of cacao in Porto Rico is the danger of wind 
storms, which may shake the entire crop from the trees. Cacao is unusually 
susceptible to this danger, since the large fruits are borne on very slender stems 
which come directly out of the inflexible wood of the larger branches or even from 
the trunk itself. 
Cacao was introduced into Porto Rico by refugees from Venezuela in the early 
part of the century, and the culture flourished for a considerable period, 
although the amount produced was never very large and has of late years 
declined, perhaps owing to the fact that the exports of other countries were more 
prominent in the markets and had easier access to the commerce of Europe and 
the United States. In some of the West Indian islands, not subject to hurricanes, 
cacao is, however, already recognized as an important product. In many parts 
of the island of Porto Rico it might be made a valuable adjunct to mixed farm- 
ing. The processes are not complicated nor costly, but some skill is required, 
and a mistake may render the beans of little or no value. 
A new cacao disease has recently appeared in Trinidad which forbids the 
importation into Porto Rico of new stock from that island without expert precau- 
tions or quarantining in a locality where no cacao trees now exist, so that plants 
which proved to be infected might be carefully destroyed before the disease could 
spread. 
Superintendent Hart of the Royal Botanic Gardens of Trinidad secured some 
years since from Nicaragua a species of cacao (Theobroma pentagona) not pre- 
viously cultivated in that island. Trees of this species have recently fruited and 
are found to be more vigorous and resistant to disease than the varieties of 
Theobroma cacao hitherto used. The fruits of 7. pentagona differ from those of 
T. cacao in having five prominent ridges or angles. In Nicaragua it is said to 
yield beans of high grade for manufacturing purposes. Successful attempts at 
grafting cacao by the method of inarching have also been made at the Trinidad 
Gardens, an achievement of vast importance to this industry, since it renders 
possible the formation of plantations of trees of uniformly high vigor and pro- 
ductiveness, which will yield a product of uniform quality, able on that account 
to command special prices in the market. 
The best cacao of Mexico from the region of Socomusco in the State of Chiapas 
does not come from 7’. cacao, but is believed to be derived from 7. angustifolia, 
a very different species, now placed in a distinct subgenus. Several other species 
are also cultivated in Central and South America, and those doubtless have more 
or less different requirements in the way of climate and soils. A careful canvass 
of the subject would be logically the first step in the direction of reestablishing a 
cacao industry in Porto Rico. 
