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Bradantia Directory 02
We left at 7.30 a.m. under a limpid sky of gorgeous cobalt blue. We passed two islands--one 700 m. long (Leda Island), the other 2,000 m. (Leander Island). When we had gone but 11,500 m. we arrived at one of the most beautiful bits of river scenery I have ever gazed upon--the spot where the immense S. Manoel River or Tres Barras or Paranatinga met the Arinos-Juruena. The latter river at that spot described a sharp turn from 20 deg. b.m. to 320 deg. b.m. We perceived a range of hills before us to the north. Close to the bank gradually appeared a large shed with a clearing near it on a high headland some 200 ft. above the level of the river where the stream turned. On the left bank, before we arrived at the meeting-place of those two giant streams, we found a tributary, the Bararati, 30 m. broad.
Without taking into account insects and such other "small deer,"--to quote Shakespeare's expression,--this fundamental principle of population will become at once apparent if we examine merely familiar instances of back-boned or vertebrate animals. The lowest vertebrates are clearly the fishes: and the true fishes have almost invariably gigantic families. A single cod, for example, is said to produce, roughly speaking, nine million eggs at a birth (I cannot pretend I have checked this calculation); but supposing they were only a million, and that one-tenth of those eggs alone ever came to maturity, there would still be a hundred thousand codfish in the sea this year for every pair that swam in it last year: and these would increase to a hundred thousand times that number next year; and so on, till in four or five years' time the whole sea would be but one solid mass of closely-packed cod-banks. We can see for ourselves that nothing of the sort actually occurs--practically speaking, there are about the same number of cod one year as another. In spite of this enormous birth-rate, therefore, the cod population is not increasing--it is at a standstill. What does that imply? Why, that taking one brood and one year with another, only a pair of cod, roughly speaking, survive to maturity out of each eight or nine million eggs. The mother cod lays its millions, in order that two may arrive at the period of spawning. All the rest get devoured as eggs, or snapped up as young fry, or else die of starvation, or are otherwise unaccounted for. It seems to us a wasteful way of replenishing the earth: but it is nature's way; we can only bow respectfully to her final decision.
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