16 DISCOLOURED SEA. [cHar. 1, 
ing. Their shape is oval, and contracted in the middle by a 
ring of vibrating curved cilie. It was, however, very difficult 
to examine them with care, for almost the instant motion ceased, 
even while crossing the field of vision, their bodies burst. Some- 
times both ends burst at once, sometimes only one, and a quan- 
tity of coarse, brownish, granular matter was ejected. The 
animal an instant before bursting expanded to half again its 
natural size; and the explosion took place about fifteen seconds 
after the rapid progressive motion had ceased: in.a few cases it 
was preceded for a short interval by a rotatory movement on the 
longer axis. About two minutes after any number were isolated 
in a drop of water, they thus perished. The animals move with 
the narrow apex forwards, by the aid of their vibratory ciliz, 
and generally by rapid starts. They are exceedingly minute, 
and quite invisible to the naked eye, only covering a space equal 
to the square of the thousandth of an inch. Their numbers 
were infinite ; for the smallest drop of water which I could re- 
move contained very many. In one day we passed through two 
spaces of water thus stained, one of which alone must have 
extended over several square miles. What incalculable numbers 
of these microscopical animals! The colour of the water, as 
seen at some distance, was like that of a river which has flowed 
through a red clay district; but under the shade of the vessel’s 
side it was quite as dark as chocolate. The line where the red 
and blue water joined was distinctly defined. The weather for 
some days previously had been calm, and the ocean abounded, to 
an unusual degree, with living creatures.* 
In the sea around Tierra del Fuego, and at no great distance 
from the land, I have seen narrow lines of water of a bright red 
colour, from the number of crustacea, which somewhat resemble 
in form large prawns. The sealers call them whale-food. 
Whether whales feed on them I do not know; but terns, cormo- 
* M. Lesson (Voyage de la Coquille, tom. i., p. 255) mentions red water 
off Lima, apparently produced by the same cause. Peron, the distinguished 
naturalist, in the Voyage aux Terres Australes, gives no less than twelve 
references to voyagers who have alluded to the discoloured waters of the sea 
(vol. ii. p. 239). To the references given by Peron may be added, Hum- - 
boldt’s Pers. Narr., vol. vi. p. 804; Flinders’. Voyage, vol. i. p. 92; Labil- 
lardiére, vol. i. p. 287; Ulloa’s Voyage; Voyage of the Astrolabe and of 
the Coquille; Captain King’s Survey of Australia, &c. : 
