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A microscopic vegetable organism, belonging to the class Algæ, usually in the form of a jointed rodlike filament, and found in putrefying organic infusions. Bacteria are destitute of chlorophyll, and are the smallest of microscopic organisms. They are very widely diffused in nature, and multiply with marvelous rapidity…

The chemistry of living organisms; the chemistry of the processes incidental to, and characteristic of, life.

A doctrine that the genesis or production of living organisms can take place only through the agency of living germs or parents; -- opposed to abiogenesis.

Pertaining to psychical phenomena in their relation to the living organism or to the general phenomena of life.

The classification of living organisms according to their structural character; taxonomy.

all protuberance on certain low forms of animals and vegetables which develops into a new organism, either free or attached. See Hydra. Bud moth (Zoöl.), a lepidopterous insect of several species, which destroys the buds of fruit trees; esp. Tmetocera ocellana and Eccopsis malana on the apple tree.

A process of asexual reproduction, in which a new organism or cell is formed by a protrusion of a portion of the animal or vegetable organism, the bud thus formed sometimes remaining attached to the parent stalk or cell, at other times becoming free; gemmation. See Hydroidea.

The sensitiveness exhibited by small free-swimming organisms, as bacteria, zoöspores of algæ, etc., to chemical substances held in solution. They may be attracted (positive chemotaxis) or repelled (negative chemotaxis). -- Chem`o*tac"tic (#), a. -- Chem`o*tac"tic*al*ly, adv.

The science which treats of the laws of distribution of living organisms over the earth's surface as to latitude, altitude, locality, etc. Its distribution or chorology. Huxley.

covering also the whole or a part of the exterior. They are also found on some vegetable organisms. In the Infusoria, and many larval forms, they are locomotive organs.

Pertaining to or connected with the cilia in animal or vegetable organisms; as, ciliary motion.

One of the round variety of bacteria, a vegetable organism, generally less than a thousandth of a millimeter in diameter.

A small, rounded, marine organism, capable of braking up into coccoliths.

hich we call its culture. Tylor. Culture fluid, a fluid in which the germs of microscopic organisms are made to develop, either for purposes of study or as a means of modifying their virulence.

Development of cells in animal and vegetable organisms. See Gemmation, Budding, Karyokinesis; also Cell development, under Cell.

The fertilized egg cell or parent cell, from the development of which the child or other organism is formed. Hæckel.

To disturb in action or function, as a part or organ, or the whole of a machine or organism. A sudden fall deranges some of our internal parts. Blair.

The series of changes which animal and vegetable organisms undergo in their passage from the embryonic state to maturity, from a lower to a higher state of organization.

The decomposition of complex substances, within the organism, into simpler ones suitable only for excretion, with evolution of energy, -- a normal nutritional process the reverse of assimilation; downward metabolism. The breaking down of already existing chemical compounds into simpler ones, sometimes called disassimil…

ogy which treats of rudimentary organs, in view of their being useless to the life of the organism. To the doctrine of dysteleology, or the denial of final causes, a proof of the real existence of such a thing as instinct must necessarily be fatal. Word (Dynamic Sociology).