PERITRACHEAL
Per`i*tra"che*al, a. (Zoöl.)
Defn: Surrounding the tracheæ.
PERITREME Per"i*treme, n. Etym: [Pref. peri- + Gr. (Zoöl.) (a) That part of the integument of an insect which surrounds the spiracles. (b) The edge of the aperture of a univalve shell.
PERITRICHA
Pe*rit"ri*cha, n. pl. Etym: [NL., fr. Gr. (Zoöl.)
Defn: A division of ciliated Infusoria having a circle of cilia around the oral disk and sometimes another around the body. It includes the vorticellas. See Vorticella.
PERITROCHIUM
Per`i*tro"chi*um, n. Etym: [NL., fr. Gr. (Mech.)
Defn: The wheel which, together with the axle, forms the axis in peritrochio, which see under Axis.
PERITROPAL
Per*it"ro*pal, a. Etym: [Gr. péritrope.]
1. Rotatory; circuitous. [R.]
2. Having the axis of the seed perpendicular to the axis of the pericarp to which it is attached.