364 BOTANICAL GAZETTE [May 
clear and limpid water. Good water is a very important item to strangers 
in a tropical country, especially in Mexico, where the streams are polluted by 
the frequent washing of clothes along their courses. The Valley of Las Canoas 
is shut in from the surrounding country by high hills, and is especially well sit- 
uated for the establishment of a tropical laboratory. The air is clear and brac- 
ing, and food is easily obtained. Easy of access to the deserts on the table land 
above by the daily trains which run on the Mexican Central railroad to San Luis 
Potosi and thence to Aguas Calientes, the locality is especially well situated 
for botanizing. From Las Canoas by means of the railroad toboggan, or by 
train, one can descend through the grand and impressive Tamasopo cafon 
into the tropics. Mr. Pringle? has described the characters of the region in 
such an interesting pen picture, that the writer cannot refrain from quoting 
him at this point : 
Gliding beside the stream of purest water issuing from the hillside cave, the train 
advances cautiously to the gate of the cafion cut out by the river formed by the stream 
which issues from the perennial spring uniting with another stream which rushes os 
enters above plunging, boiling waters. Then for eight or nine miles the roadbed has 
been cut in the rock of the steep mountain side, or has been laid on wa 
spring from far below. On such dizzy heights the train hangs and sways and winds 
through constantly occurring curves. Where mountain buttresses interpose, tunnels 
open a way, till eight are passed. Within the cafion long vistas of the wildest moun- 
tain scenery open before us. The opposite mountain side is precipitous in places, '» 
: re 
others cut by gorges. It is everywhere covered with a variety of trees, except “8 
built his hut 
we are looking down upon a fertile hacienda, on broad open valleys strete 
low hills, which are covered with heavy tropical forests, on meadows with § : 
herds, and on broad fields of corn and cane. In making the descent nr med 
tain side to Tamasopo siding, the road turns back upon itself in mnie = be 
At the foot of the mountain it passes through a heavy forest in whose s - 7 oper 
plantation. The region is in the one of heaviest rainfall. The winds, ' os 
laden with moisture which arises from the Gulf, are repelled from the —— os 
to precipitate on these mountains torrents of rain, as their temperature is caper 
their ascending into cuoler regions of air. Yet the temperature of ate HE of so 
a little lower than that of the coast, is still a tropical heat ; and from conditio 
} . forests, com 
great heat and moisture results a vegetation of great luxuriance. rates aaa 
posed of numerous ‘species, are thick, the undergrowth beneath the jmost 
to f an 4 
and trees and shrubs are bound together by clambering vines and leaning 
apace. The most abundant tree of these tropical forests is i 
Segoviae, with smooth gray bark, and often of vast size, espe¢! 
? Garden and Forest 6: 182, 203. 1893. 
