The Naturalist in La Plata | Page 8

organ, with the
correlated instinct, to rest without use, yet ready to flash forth on the
instant, bright and keen-edged, as in the ancient days of strife, ages past,
before peace came to dwell on earth!
The avi-fauna is relatively much richer than the mammalia, owing to
the large number of aquatic species, most of which are migratory with
their "breeding" or "subsistence-areas" on the pampas. In more senses
than one they constitute a "floating population," and their habits have in
no way been modified by the conditions of the country. The order,
including storks, ibises, herons, spoonbills, and flamingoes, counts
about eighteen species; and the most noteworthy birds in it are two
great ibises nearly as large as turkeys, with mighty resonant voices. The
duck order is very rich, numbering at least twenty species, including
two beautiful upland geese, winter visitors from Magellanic lands, and
two swans, the lovely black-necked, and the pure white with rosy bill.
Of rails, or ralline birds, there are ten or twelve, ranging from a small
spotted creature no bigger than a thrush to some large majestic birds.
One is the courlan, called "crazy widow" from its mourning plumage
and long melancholy screams, which on still evenings may be heard a
league away. Another is the graceful variegated _ypicaha,_ fond of
social gatherings, where the birds perform a dance and make the
desolate marshes resound with their insane humanlike voices. A
smaller kind, Porphyriops melanops, has a night-cry like a burst of
shrill hysterical laughter, which has won for it the name of "witch;"
while another, Rallus rythyrhynchus, is called "little donkey" from its
braying cries. Strange eerie voices have all these birds. Of the
remaining aquatic species, the most important is the spur-winged
crested screamer; a noble bird as large as a swan, yet its favourite
pastime is to soar upwards until it loses itself to sight in the blue ether,
whenca it pours forth its resounding choral notes, which reach the
distant earth clarified, and with a rhythmic swell and fall as of chiming
bells. It also sings by night, "counting the hours," the gauchos say, and
where they have congregated together in tens of thousands the mighty
roar of their combined voices produces an astonishingly grand effect.

The largest aquatic order is that of the Limicolse--snipes, plover, and
their allies--which has about twenty-five species. The vociferous
spur-winged lapwing; the beautiful black and white stilt; a true snipe,
and a painted snipe, are, strictly speaking, the only residents; and it is
astonishing to find, that, of the five-and-twenty species, at least thirteen
are visitors from North America, several of them having their
breeding-places quite away in the Arctic regions. This is one of those
facts concerning the annual migration of birds which almost stagger
belief; for among them are species with widely different habits, upland,
marsh and sea-shore birds, and in their great biannual journey they pass
through a variety of climates, visiting many countries where the
conditions seem suited to their requirements. Nevertheless, in
September, and even as early as August, they begin to arrive on the
pampas, the golden plover often still wearing his black nuptial dress;
singly and in pairs, in small flocks, and in clouds they come--curlew,
godwit, plover, tatler, tringa--piping the wild notes to which the
Greenlander listened in June, now to the gaucho herdsman on the green
plains of La Plata, then to the wild Indian in his remote village; and
soon, further south, to the houseless huanaco-hunter in the grey
wilderness of Patagonia.
Here is a puzzle for ornithologists. In summer on the pampas we have a
godwit--Limosa hudsonica; in March it goes north to breed; later in the
season flocks of the same species arrive from the south to winter on the
pampas. And besides this godwit, there are several other North
American species, which have colonies in the southern hemi-spere,
with a reversed migration and breeding season. Why do these southern
birds winter so far south? Do they really breed in Patagonia? If so, their
migration is an extremely limited one compared with that of the
northern birds--seven or eight hundred miles, on the outside, in one
case, against almost as many thousands of miles in the other.
Considering that some species which migrate as far south as Patagonia
breed in the Arctic regions as far north as latitude 82 degrees, and
probably higher still, it would be strange indeed if none of the birds
which winter in Patagonia and on the pampas were summer visitors to
that great austral continent, which has an estimated area twice as large
as that of Europe, and a climate milder than the arctic one. The

migrants would have about six hundred miles of sea to cross from
Tierra del Fuego; but we know that the golden plover and