Jan., 1889. “the naturalist in Nicaragua.” 21 
ants are sometimes several hundred yards in length, reaching 
from the formicarium, or ant city*, to the feeding ground. On 
closer examination a double stream of these minute pests, one 
laden with leaves, looking like a mimic “forest of Birnam,” 
the other empty-handed and returning each for a leaf. The 
leaves are cut off with the sharp scissor-like jaws of the ant, 
clinging hold by one leg so that the leaf does not fall off. Mr. 
Belt actually satisfied himself that these leaves were carried 
to the formicarium, not to be eaten or used in forming the 
nest, but for the purpose of growing a minute fungus, upon 
which the ants feed—in fact, they are regular mushroom 
growers ! The following, among many others, is adduced as 
an instance of the reasoning powers of these wonderful little 
animals:—“A nest was made near one of our tramways, and 
to get to the trees the ants had to cross the rails, over which 
the waggons were continually passing and re-passing. Every 
time they came along a number of ants were crushed to death. 
They persevered in crossing for several days, but at last set 
to work and tunnelled underneath each rail. One day when 
the waggons were not running, I stopped, up the tunnels with 
stones; but although great numbers carrying leaves were 
thus cut off from the nest, tliev would not cross the rails, 
but set to work making fresh tunnels underneath them. 
Apparently an order had gone forth, or a general under¬ 
standing been come to, that the rails were not tc be 
crossed.” The third form of ant studied by the author 
was that tenanting the interior of the “ bull’s horn 
thorn,” a curious plant of the Acacia tribe, belonging to 
the Gummifera, with bi-pinnate leaves, growing to a height 
of 20 feet. It is a most remarkable case of commensalism. 
No harm is apparently done by the ants to the plant, 
for, notwithstanding that they feed on its honey-like 
juice, they in return protect it from the ravages of other 
insects (as these ants sting powerfully), especially those of 
their leaf-bearing congeners. The tricks recorded by the 
author of a tame white-faced cebus monkey were most 
curious and strangely human. It would tempt ducklings 
within reach by a piece of bread, and then kill them by a bite 
on the breast; it would pick pockets, pull out letters and take 
them out of the envelopes. “Once he abstracted a small 
bottle of turpentine from the pocket of our medical officer. 
He drew the cork, held it first to one nostril then to the 
other, made a wry face, re-corked it, and returned it to the 
doctor ! ” The humming birds noticed were both numerous 
and beautiful, and there is an instance recorded of their 
fertilising a rare pitcher plant (Marcgravia nepenthoidesj. 
