PER- 



236 



PHA- 



Dividing a valve longitudinally 

 (bot.}. 



pervious (per'vius) a. [L.per, through ; 

 via, a way.] Perforated ; permeable 

 (btol.} ; appl. nostrils with no septum 

 between the nasal cavities (zool.}. 

 pes (pez) n. [L. pes, foot.] A foot or 

 foot-like structure ; as certain parts 

 of the brain, branches of the facial 

 nerve (anat.}. 



pessulus (peVulus) n. [L. pessulus, a 

 bolt.] An internal skeletal element 

 in the syrinx of some Birds, 

 petal (pet'al) n. \Gk.petalon, a petal.] 

 One of the separate parts of a 

 corolla (bot.}. 



petaliform (pgtal'iform) a. [Gk. 

 petalon, petal ; L. forma, shape.] 

 Petal-shaped ; petal-like ; petaloid ; 

 petaline. 



petalled (peVald) a. [Gk. petalon, a 

 petal.] With petals ; petaliferous ; 

 opp. apetalous (bot.}. 

 petalody (pgtal'ddi) n. [Gk. petalon, 

 petal : eidos, resemblance.] Con- 

 version of other parts of a flower 

 into petals (hot.). 



petaloid (p&'aloid) a. [Gk. petalon, 

 petal ; eidos, resemblance.] Like a 

 petal (biol.} ; appl. the ambulacral 

 areas of certain Echinoderms (zool.}. 

 petaloideous (pet'aloid'eus) a. [Gk. 

 petalon, petal ; eidos, resemblance.] 

 Petaloid ; appl. monocotyledons 

 with coloured perianth (bot}. 

 petasma (ptaz'ma) n. \Gk.petasma, 

 anything spread out.] A compli- 

 cated membranous plate on the 

 inner side of the peduncle with 

 interlocking coupling hooks, an 

 apparatus of certain Crustacea 

 (zool.}. 



petiolar (pgt'iolar) a. [L. petiolus, 

 a little foot.] Pert, having, or 

 growing on a small stalk (bot.}. 

 petiolate (pgt'iolat) a. [L. petiolus, 

 a small foot.] Growing on a petiole 

 (bot.} ; having thorax and abdomen 

 connected by a petiole (zool.}. 

 petiole (pet'iol) n. [L. petiolus, a 

 small foot.] The foot-stalk of a 

 leaf (bot.} ; a slender stalk connect- 

 ing thorax and abdomen in Insects 

 (zool.}. 



petiolule (pgt'io'lul) n. [L. petiolus, 

 a small foot.] The foot-stalk of a 

 leaflet of a compound leaf (bot.}. 



petrohyoid (pet'rohi'oid) a. [Gk. 

 petros, stone ; hyoeides, Y-shaped.] 

 Pert, hyoid and petrous part of 

 temporal (anat.}. 



petromastoid (pet'romas'toid) a. [Gk. 

 petros, stone ; mastos, breast.] Pert. 

 the mastoid process and the petrous 

 portion of the temporal (anat.}. 

 petrooccipital (pet'rooksip'ital) a. 

 [Gk. petros, stone ; L. occipzit, back 

 of the head.] Pert, occipital and 

 petrous part of temporal ; appl. a 

 fissure (anat.}. 



petrosal (pgtro'sal) a. [Gk. petros, 

 stone.] Solidly bony ; appl. a 

 sphenoidal process, a ganglion of 

 the glossopharyngeal, to nerves and 

 sinus in the region of the petrous 

 portion of the temporal bone (anat.}; 

 appl. the otic bones of Fishes (zool. }. 

 petrosphenoidal (pet'rosfenoid'al) a. 

 [Gk. petros, stone ; sphen, wedge.] 

 Pert, sphenoid and petrous part of 

 temporal ; appl. a fissure (anat.}. 

 petrosquamosal (pet'roskwamo'sal) a. 

 [Gk. petros, stone ; L. squama, 

 scale.] Pert, squamosal and petrous 

 part of temporal ; appl. sinus and 

 suture (anat.}. 



petrotympanic (pSt'rotimpan'ik) a. 

 \G\a.petros, stone ; tympanon, drum.] 

 Pert, tympanum and petrous por- 

 tion of temporal ; appl. a fissure 

 (anat.}. 



petrous (pet'riis) a. [Gk. petros, 

 stone.] Very hard or stony ; appl. 

 a pyramidal portion of the tem- 

 poral .bone wedged in between 

 sphenoid and occipital ; also a 

 ganglion on its lower border 

 (anat.}. 



Peyer's patches, oval patches of 

 aggregated lymph follicles on the 

 intestine walls (zool.}. 

 phacella (fasgl'a) n. [Gk. phakelos, 

 a bundle of faggots.] A delicate 

 filament with mesogloea core, and 

 supplied with stinging capsules, 

 occurring in rows in the stomach 

 of certain Coelenterates (zool.}. 

 phacoid (fak'oid) a. [Gk. phako, a 

 lentil ; eidos, resemblance.] Lentil- 

 shaped. 



phaeism (fe'izm) n. [Gk. phaios, 

 dusky.] Duskiness ; appl. the 

 colouring of butterflies, 

 phaeochrome (fe'okrom) n. [Gk. 



