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Vengeance, instinct of. Venus Erycina, priestesses of. Vermes. Vermiform appendage. Verreaux, M., on the attraction of numerous males by the female of an Australian Bombyx. Vertebrae, caudal, number of in macaques and baboons; of monkeys, partly imbedded in the body. Vertebrata, common origin of the; most ancient progenitors of; origin of the voice in air-breathing.
A corresponding germinal condition, the two-layered gastrula, occurs transitorily in the embryological history of all the other Metazoa, from the lowest Cnidaria and Vermes up to man. From the common stock of the Helminthes, or simple worms, there develop as independent main branches the four separate stems of the Molluscs, Star-fishes, Arthropods, and Vertebrates.
Hence the difficulties which have embarrassed the naturalists, who adopt the Linnæan classification, in their endeavours to discover determinate characters of distinction between the vermes and the insecta. But no sooner have we passed the borders, than endless variety of form and the bold display of instincts announce, that Nature has succeeded.
With the ascent in power, the intensity of individuation keeps even pace; and from this we may explain all the characteristic distinctions between this class and that of the vermes. The almost homogeneous jelly of the animalcula infusoria became, by a vital oxydation, granular in the polypi.
Linnæus asserts, "that it grows old at one extremity, while it continues to generate young ones at the other, proceeding ad infinitum, like a root of grass. The separate joints are called gourd-worms, and propagate new joints like the parent without end, each joint being furnished with its proper mouth, and organs of digestion." Systema naturæ. Vermes tenia.
The proof of these statements is to be found in the fact that many infants expel both these varieties of parasites with the first stool. It is difficult to know what to make of these opinions; for, with the exception of certain cases in some of the seventeenth and eighteenth century writers, there are no records in medicine of the occurrence of vermes in the infant at birth.
There is still another class of animals, which are termed vermes by Linnæus, which are without feet, or brain, and are hermaphrodites, as worms, leeches, snails, shell-fish, coralline insects, and sponges; which possess the simplest structure of all animals, and appear totally different from those already described.
They hardly appear like animals, and consist of a simple, tough, leathery sack, with two small projecting orifices. They belong to the Mulluscoida of Huxley a lower division of the great kingdom of the Mollusca; but they have recently been placed by some naturalists amongst the Vermes or worms.
But in this and the foregoing classes, as being still near the common equator, or the punctum indifferentiæ, the carbonic principle still asserts its claims, and the force of reproduction struggles with that of irritability. In the unreconciled strife of these two forces consists the character of the Vermes, which appear to be the preparatory step for the next class.
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