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The distal segment of the hind limb of vertebrates, including the tarsus and foot.

A group of invertebrates including the Tunicata and Enteropneusta. -- Pha*ryn`gop*neus"tal, a.

nd the esophagus. It has one or two external openings through the nose in the higher vertebrates, and lateral branchial openings in fishes and some amphibias.

of changes, as in the changes of motion of one of the particles constituting a wave or vibration; one portion of a series of such changes, in distinction from a contrasted portion, as the portion on one side of a position of equilibrium, in contrast with that on the opposite side.

A lover of the truth. [Obs.] Brathwait.

tylus attached to some point of the membrane records the movements of the latter, as it vibrates, upon a moving cylinder or plate.

n enough to give colored bands, the form and position of which are affected by sonorous vibrations.

nfoil, wax, paraffin, etc., above which is a thin plate carrying a stylus. As the plate vibrates under the influence of a sound, the stylus makes minute indentations or undulations in the soft material, and these, when the cylinder or disk is again turned, set the plate in vibration, and reproduce the sound.…

An instrument for measuring sounds, as to their intensity, or the frequency of the vibrations.

An instrument in which motion is produced by the vibrations of a sounding body.

An instrument for producing luminous figures by the vibrations of sounding bodies.

ne. Pineal gland (Anat.), a glandlike body in the roof of the third ventricle of the vertebrate brain; -- called also pineal body, epiphysis, conarium. In some animals it is connected with a rudimentary eye, the so-called pineal eye, and in other animals it is supposed to be the remnant of a dorsal median eye.…

The class of Vertebrata that includes the fishes. The principal divisions are Elasmobranchii, Ganoidei, and Teleostei.

The relative acuteness or gravity of a tone, determined by the number of vibrations which produce it; the place of any tone upon a scale of high and low.

A disciple of Plotinus, a celebrated Platonic philosopher of the third century, who taught that the human soul emanates from the divine Being, to whom it reunited at death.

A chitinous structure which supports the gill in some invertebrates.

ited species of this genus are harmless. The tree (Rhus vernicifera) which yields the celebrated Japan lacquer is almost identical with the poison sumac, and is also very poisonous. The juice of the poison sumac also forms a lacquer similar to that of Japan.

A grand division of the Invertebrata, including the sponges; -- called also Spongiæ, Spongida, and Spongiozoa. The principal divisions are Calcispongiæ, Keratosa or Fibrospongiæ, and Silicea.

A celebrated cinerary urn or vase found in the tomb of the Emperor Alexander Severus. It is owned by the Duke of Portland, and kept in the British Museum.

nd, or on the caudal or posterior (that is, ulnar or fibular) side of, the axis of a vertebrate limb.