Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 25, 2025
In some cases, however, the mature animal must be considered as lower in the scale than the larva, as with certain parasitic crustaceans. To refer once again to cirripedes: the larvae in the first stage have three pairs of locomotive organs, a simple single eye, and a probosciformed mouth, with which they feed largely, for they increase much in size.
Flocks of fish, if we can use such an expression, escaped on all sides from the dense thickets like flocks of birds. It seemed as though the thousand pieces of a broken mirror glimmered through the waters. At the same time scores of crustaceans scampered over the sand, like huge ants hurrying from their hills.
It is not known that male crustaceans fight together for the possession of the females, but it is probably the case; for with most animals when the male is larger than the female, he seems to owe his greater size to his ancestors having fought with other males during many generations.
In certain crustaceans, for instance, there is a double cornea, the inner one divided into facets, within each of which there is a lens-shaped swelling.
Every one knows how the horns of stags become more and more branched, and the plumes of some birds become more finely developed, as they grow older. Professor Cope states that the teeth of certain lizards change much in shape with advancing years. With crustaceans not only many trivial, but some important parts assume a new character, as recorded by Fritz Muller, after maturity.
Among the swarm of small crustaceans moving around on the sandy bottom, hunting, eating, or fighting with a ferocious entanglement of claws, the onlookers always search for a bizarre and extravagant little creature, the paguro, nicknamed "Bernard, the Hermit." It is a snail that advances upright as a tower, upon crab claws, yet having as a crown the long hair of a sea-anemone.
It would not, for instance, at first occur to any one that the transparency of the Medusae, or jelly-fish, is of the highest service to them as a protection; but when we are reminded by Haeckel that not only the Medusae, but many floating Mollusca, crustaceans, and even small oceanic fishes partake of this same glass-like appearance, often accompanied by prismatic colours, we can hardly doubt that they thus escape the notice of pelagic birds and other enemies.
We may remark that other classes of animals exuviate in a similar manner to the crustaceans. Thus serpents throw off in entire masses their scaly coverings, even a slough from the eyes; and various insects in their larva state are continually throwing off and renewing their skins. Pp. 120-122.
We spent the whole day of February 22 in the Sargasso Sea, where fish that dote on marine plants and crustaceans find plenty to eat. The next day the ocean resumed its usual appearance. From this moment on, for nineteen days from February 23 to March 12, the Nautilus stayed in the middle of the Atlantic, hustling us along at a constant speed of 100 leagues every twenty-four hours.
In other crustaceans the transparent cones which are coated by pigment, and which properly act only by excluding lateral pencils of light, are convex at their upper ends and must act by convergence; and at their lower ends there seems to be an imperfect vitreous substance.
Word Of The Day
Others Looking