Evening star. [volume] (Washington, D.C.) 1854-1972, 1879-06-14
The Rats in Brazil.

From time to time In all parts of Brazil the
plantations are subject to the depredati0ns OF
consume everything edible that comes in their
way. During recent excursion In the Pro-
vince OF Parana Mr.. Derby found an almost
universal lack OF corn throughout the Province
due to such invasion OF rats, by which almost
the entire crop OF last year had been destroyed
This Invasion, Or plague as 1t Is called, Is said
to occur at Intervals OF about thirty years, and
to be simultaneous with the drying Of the
tdQuGra, or bamboo, which everywhere abouuds
In the Brazilian forests. The popular eXplaua
ton Is that every cane Of bamboo sprouts
with gruO, the germ OF rat, within it, and
that when the bamboo ripens and dies the germ
becomes fully developed rat and comes out to
prey on the plantations. An educated and
observant EnglShman, Mr.. Herbert III. Mercer
who has resided a number OF years In the
province ana had an opportunity OF study
Ing the phenomenon, furnished Mr.. Derby
the following rational and curious explanation
The bamboo arrives at maturity, flowers ard
seeds at intervals OF several years, which
doubtless vary with the different species. The
period for the species most abundant In Parana
Is 80 years. The process instead of being
simultaneous, occupies about five years. a few
of the canes going to seed the first year. an
gressively, till finally the remaining and larger
POI tion OF the canes seed at the same time. lch
cane bears about peck OF edible seed. resen-
bling rice. which IS very fat and nouri shing,
and Is often eaten by the Indians. The quantity
produced Is enormous, and large areas are often
covered to depth of five or six inches. After
seeing, the cane 0loS, breaks OH at the root aud
falls to the ground, the process OF decay being
fastened by the borings Of larva which live
upon the bamboo and appear to be particularly
abundant at seeding time. These larva have
doubtless given rise to the story of the grub
developing into a rat. New canes spring rp
from the seed. but require seven or eight years
10 become MT for use, and 80 to reach maturity
With the sudden and constantly increasing suD-
ply OF nourishing food for period of five years,
the rats and mice, both Of native and imported
species, increase extraordinarily in numbers
The fecundity OF these animals Is well known,
and the result after four or five years of an uu
usual and constantly increasing supply of ex
cellent food and In the absence OF enemies or
equal fecundity, can readily be imagined The
last OF the crop OF seed being mature and fallen
to the ground, the first rain causes 1t to decay
In the space OF very few days. The rats, sud
denly deprived OF food, commence to migrate,
invading the plantations and houses, and con.
Stunning everything that does not happen to be
repugnant to the not very fastidious palate OF a
furnishing rodent. II this happens at the time
OF complaining, the seed is consumed as IA
as II can be put into the ground. The mandloca
Is dug up: the rice crop, If It happens to be
newly sown or in seed, Is consumed, as is also
everything In the houses In the way OF pro.
Visions and leather, II not carefully guarded In
TIN trunkS.-TN1 Nature