Part 642

Psy`cho*zo"ic (?), a. [Psycho- + Gr. &?; life.] (Geol.)Designating, or applied to the Era of man; as, the psychozoic era.

Psy*chrom"e*ter (?), n. [Gr. psychro`s cold + -meter: cf. F. psychromËtre.] An instrument for measuring the tension of the aqueous vapor in the atmosphere, being essentially a wet and dry bulb hygrometer.

Psy`chro*met"ric*al (?), a. Of or pertaining to the psychrometer or psychrometry.

Psy*chrom"e*try (?), n. Hygrometry.

||Psyl"la (?), n.; pl. PsyllÊ (#). [NL., from Gr. &?; a flea.] (Zoˆl.) ||Any leaping plant louse of the genus Psylla, or family PsyllidÊ.

Ptar"mi*gan (?), n. [Gael. tarmachan; cf. Ir. tarmochan, tarmonach.] (Zoˆl.) Any grouse of the genus Lagopus, of which numerous species are known. The feet are completely feathered. Most of the species are brown in summer, but turn white, or nearly white, in winter.

They chiefly inhabit the northern countries and high mountains of Europe, Asia, and America. The common European species is Lagopus mutus. The Scotch grouse, red grouse, or moor fowl (L. Scoticus), is reddish brown, and does not turn white in winter. The white, or willow, ptarmigan (L. albus) is found in both Europe and America.

||Pte`no*glos"sa (?), n. pl. [NL., fr. Gr.&?; feathered + &?; tongue.] ||(Zoˆl.) A division of gastropod mollusks having the teeth of the ||radula arranged in long transverse rows, somewhat like the barbs of a ||feather.

Pte`no*glos"sate (?), a. (Zoˆl.) Of or pertaining to the Ptenoglossa.

Pte*ran"o*don (?), n. [Gr. &?; wing + &?; priv. + &?;, &?;, a tooth.] (Paleon.) A genus of American Cretaceous pterodactyls destitute of teeth. Several species are known, some of which had an expanse of wings of twenty feet or more.

||Pte*ran`o*don"ti*a (?), n. pl. [NL.] (Paleon.) A group of ||pterodactyls destitute of teeth, as in the genus Pteranodon.

||Pte*rich"thys (?), n. [NL., fr. Gr. &?; wing + &?; fish.] (Paleon.) A ||genus of Devonian fossil fishes with winglike appendages. The head ||and most of the body were covered with large bony plates. See ||Placodermi.

Pter`i*dol"o*gist (?), n. One who is versed in pteridology.

Pter`i*dol"o*gy (?), n. [Gr. &?;, &?;, a fern + -logy.] That department of botany which treats of ferns.

Pter`i*do*ma"ni*a (?), n. [Gr. &?;, &?;, a fern + E. mania.] A madness, craze, or strong fancy, for ferns. [R.] C. Kingsley.

||Pter`i*doph"y*ta (?), n. pl. [NL., from Gr. &?;, &?;, a fern + &?; a ||plant.] (Bot.) A class of flowerless plants, embracing ferns, ||horsetails, club mosses, quillworts, and other like plants. See the ||Note under Cryptogamia. -- Pter"i*do*phyte` (#), n.

This is a modern term, devised to replace the older ones acrogens and vascular Cryptogamia.

||Pter`o*bran"chi*a (?), n. pl. [NL., fr. Gr. &?; a wing + &?; &?;.] ||(Zoˆl.) An order of marine Bryozoa, having a bilobed lophophore and ||an axial cord. The genus Rhabdopleura is the type. Called also ||Podostomata. See Rhabdopleura.

||Pte*roc"e*ras (?), n. [NL., fr. Gr. &?; a wing + &?; a horn.] (Zoˆl.) ||A genus of large marine gastropods having the outer border of the lip ||divided into lobes; -- called also scorpion shell.

||Pter`o*cle"tes (?), n. pl. [NL., fr Pterocles, the typical genus, fr. ||Gr. &?; feather + &?;, &?;, a key, tongue of a clasp.] (Zoˆl.) A ||division of birds including the sand grouse. They are in some ||respects intermediate between the pigeons and true grouse. Called ||also PteroclomorphÊ.

Pter`o*dac"tyl (?), n. [Gr. &?; a wing + &?; finger, toe: cf. F. ptÈrodactyle.] (Paleon.) An extinct flying reptile; one of the Pterosauria. See Illustration in Appendix.

||Pter`o*dac"ty*li (?), n. pl. [NL.] (Paleon.) Same as Pterosauria.

Pter`o*glos"sal (?), a. [Gr. &?; a feather + &?; tongue.] (Zoˆl.) Having the tongue finely notched along the sides, so as to have a featherlike appearance, as the toucans.

Pte"ron (?), n. [NL., fr. Gr. &?; a wing.] (Anat.) The region of the skull, in the temporal fossa back of the orbit, where the great wing of the sphenoid, the temporal, the parietal, and the frontal hones approach each other.

||Pter`o*pap"pi (?), n. pl. [NL., from Gr. &?; a feather, a bird + &?; ||a grandfather.] (Zool.) Same as OdontotormÊ.

Pter"o*phore (?), n. [Gr. &?; a feather + &?; to bear.] (Zoˆl.) Any moth of the genus Pterophorus and allied genera; a plume moth. See Plume moth, under Plume.

Pter"o*pod (?), n. [Gr. &?; wing-footed; &?; a feather, wing + &?;, &?;, foot: cf. F. ptÈropode.] (Zoˆl.) One of the Pteropoda.

||Pte*rop"o*da (?), n. pl. [NL.] (Zoˆl.) A class of Mollusca in which ||the anterior lobes of the foot are developed in the form of broad, ||thin, winglike organs, with which they swim at near the surface of ||the sea.