PIS- 



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piscicolous (pisik'olus) a. [L. piscis, 

 fish ; colere, to inhabit.] Living 

 within fishes, as certain parasites 

 (zool.). 



pisciform (pis'iform) a. [L. piscis, 

 fish ; forma, shape.] Shaped like 

 a fish. 



piscivorous (pisiv'orus) a. [L. piscis, 

 fish ; vorare, to devour!] Fish- 

 eating. 



pisiform (pl'siform) a. [L. pisum, a 

 pea ; forma, shape.] Pea-shaped ; 

 appl. a carpal bone (zool.). 

 pisohamate (pi'soham'at) a. [L. 

 pisum, pea ; hamus, a hook.] Appl. 

 a ligament connecting pisiform and 

 hamate bones (anat.). 

 pisometacarpal (pl'somet'akar'pal) a. 

 [L. pisum, pea ; Gk. meta, beyond ; 

 L. carpus, wrist.] Appl. a ligament 

 connecting the pisiform bone with 

 the fifth metacarpal (anat.}. 

 pistil (pTs'tll) n. [L. pistillum, a 

 pestle.] The seed-bearing organ 

 of a flower, consisting of ovary and 

 stigma (bot.). 



pistillate (pis'tilat) a. [L. pistillum, 

 a pestle.] Bearing pistils or female 

 reproductive organs (bot.). 

 pistillidium (pistilid'ium) n. [L. 

 pistillum, a pestle.] The female 

 sexual organ of Bryophytes, 

 Pteridophytes, and Gymnosperms 

 (bot.). 



pistillody (pis'tllodi) n. [L. pistillum, 

 a pestle ; Gk. eidos, resemblance.] 

 The conversion of any organ of a 

 flower into carpels (bot.). 

 pistillum (ptstil'um) n. [L. pistillum, 

 a pestle.] A mass of muscle in a 

 chitinous tube in the aurophore of 

 a medusoid colony (zool.). 

 pit (pit) n. [h..S.pyt, a pit.] A de- 

 pression formed in the course of 

 cell-wall thickening in plant tissue 

 (bot.} ; an embryonic olfactory 

 depression (smb.}. 



pitcher (pit'sher) n. [L.L. picarium, 

 a beaker.] A modification of a leaf 

 for insect-catching purposes, as the 

 pitcher-shaped leaf of Nepenthes 

 (bot.}. 



pith (pith) n. [A.S./z'Ma, pith.] The 



medulla or central region of a 



dicotyledonous stem (bot.). 



pituitary (pitu'itari) a. [L. pituita, 



phlegm.] Appl. a' body or hypo- 



physis of the hypothalamus of the 

 brain (anat.). 



pivot joint, a trochoid joint, or one 

 in which the movement is limited 

 to rotation (phys.). 



placenta (plasen'ta) n. [L. placenta, 

 a flat cake.] The ovule-bearing 

 part of the carpel (bot.) ; in eutherian 

 Mammals, a double vascular spongy 

 structure formed by interlocking of 

 foetal and maternal tissue in the 

 uterus, and in which maternal and 

 foetal blood are in close proximity, 

 allowing nutritive and respiratory 

 elements to pass from the former to 

 the latter by osmosis. 



placental (plasen'tal) a. [L. placenta, 

 a flat cake.] Pert, a placenta or 

 similar structure ; appl. Mammals 

 which develop a placenta. 



placentate (plasen'tat) a. {L. placenta, 

 a flat cake.] Having a placenta 

 developed (biol,). 



placentation (plas'enta'shun) n. [L. 

 placenta, a flat cake.] The manner 

 in which seeds are attached to the 

 pericarp, whether axile, central, 

 marginal, or parietal (bot.). 



placentiferous, placentigerous, pla- 

 centate. 



placochromatic (plak'okromat'ik) a. 

 [Gk. plax, a plate ; chroma, colour.] 

 With plate-arrangement of chrom- 

 atophores (cyt.). 



placoid (plak'oid) a. [Gk. plax, a 

 plate ; eidos, resemblance.] Plate- 

 like ; appl. the hard scales or dermal 

 teeth on the external surface of 

 Elasmobranchs (zool.). 



placula (plak'ula) n. \G\a.plax, plate.] 

 A flattened blastula with small 

 segmentation cavity, an embryonic 

 stage of Urochords (emb.). 



plagiotropic (pla'jiotrop'ik) a. [Gk. 

 plagios, oblique ; trope, a turning.] 

 Obliquely inclined ; appl. roots and 

 branches (bot.). 



plagiotropism (pla'jiot'rb'pizm) n. 

 [Gk. plagios, oblique ; trope, a 

 turning.] Tendency to incline 

 from the vertical line (bot.). 



plagiotropous (pla'jiot'ropus) a. [Gk. 

 plagios, oblique ; trope, a turning.] 

 Obliquely inclined ; appl. the asym- 

 metrical polar cap of Rhombozoa 

 (zool.). 



planiform (pla'niform) a. [L. planus, 



