I 
j 94 VEGETABLE PRODUCTIONS. 
The warm, humid valleys 'of the Gulf shore appear to be the 
natural position for the banana, where the fruit is occasionally 
eight inches in circumference, with a length of ten or twelve. 
Forty plants growing on a space of 1070 feet are calculated to 
furnish 4400 pounds of nutritive matter, a quantity above the acre- 
able produce of any cereal crop. In other words, the same ex- 
tent of ground under bananas, which will support fifty individ- 
uals, when under wheat, will only support two. 
One of the peculiar productions of these latitudes is the tree- 
fern : its natural locality is at an elevation of 5000 feet, where 
the mean temperature is 66°. It is somewhat abundant between 
the Jaltepec and Sarabia rivers, and its trunk attains a diame- 
ter of between five and six inches. These arborescent ferns are 
singularly beautiful, from the depth of the green tint of the foli- 
age and the graceful earing of the young fronds not yet unfolded, 
and which open out at the top of the tree. They are now con- 
fined within a narrow zone north and south of the equator on 
this hemisphere, and are the representatives of a large mass of 
fossil vegetation. Much of the woody matter of coal is made 
up of ancient tree-ferns. 
In a country like Mexico, where the reproductions of nature 
are so rapid, it is but reasonable to suppose that there are cor- 
responding elements of decay ; nor is it affirmed that the Isth- 
mus is entirely free from the destroying influences with which 
the regions of the tropics and the equator are usually so preg- 
nant. But the effects arising from temperature, humidity, and 
the noxious character of the numerous insect tribes, are greatly 
modified by the abundance of such woods as are proof against 
their incursions. So far, therefore, as the immediate and neces- 
sary purposes of construction are concerned, there will be found 
no lack of durable timber on the Isthmus. Among these we 
may enumerate the guapaque, which may be considered first. 
In the Parroquia, at Tehuantepec, built by Cocijopi, last cacique 
of the Zapotecos, in 1530, the staircase is made of guapaque, 
which to this time exhibits no evidences of decay. Another 
instance of the durability of this valuable wood occurs at Boca 
del Monte, in the uprights of a little chapel, which have been 
buried in the ground for more than twenty-five years, and are 
