PRA- 



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PRE- 



The anterior part of the notum of 

 an insect thoracic ring (zool.}. 



praesphenoid (pra-, presfe'noid) n. 

 [L. prae, before ; Gk. sphen, wedge.] 

 The anterior part of the sphenoid 

 (0M*). 



praesternal (pra-, presteYnal) a. [L. 

 prae, before ; sternum, breast-bone.] 

 Appl. the jugular notch, on the 

 superior border of the sternum 

 (anat.). 



preaxlal (preak'slal) a. [L. prae, 

 before ; axis, axle.] In front of 

 the axis. 



precava (preka'va) n. \L..prae, before ; 

 cavus, hollow.] The anterior vena 

 cava ; the precaval vein (zool.). 



precentral (presen'tral) a. [L. prae, 

 before ; centrum, centre.] An- 

 teriorly to the centre ; appl. a 

 sulcus parallel to the central sulcus 

 of the cerebrum (anat.~). 



prechordal (prekor'dal) a, [L. prae, 

 before ; Gk. chorde, a cord.] An- 

 teriorly to the notochord or spinal 

 cord ; appl. part of the base of the 

 skull (emb.\ 



precipitin (preslp'ltln) n. \L.praeceps, 

 headlong.] A precipitate developed 

 in blood serum (phys.). 



preclival (preklfval) a. [L. prae, 

 before ; clivus, hill.] Appl. a 

 fissure in front of the clivus of the 

 cerebellum (anat.~). 



precoracoid (prekor'akoid) . [L. 

 prae, before ; Gk. korax, crow.] 

 An anterior ventral bone of the 

 pectoral girdle of higher vertebrates 

 (zool.}. 



predelineation (pre'dellnea'shun) n. 

 [L. prae, before ; de, down ; linea, 

 a line.] Formation and individual- 

 ization of the various physiological 

 molecules in definite areas and 

 substances of the undevelopedegg, 

 the theory of germinal localization 

 (biol.}. 



predentary (predSn'tarl) . [L. prae, 

 before ; dens, tooth.] A bone at 

 the tip of the jaw of many Dinosaurs 

 (Pal.}. 



preepistome (prefip'istom) n. [L.prae, 

 before ; Gk. epi, upon ; stoma, 

 mouth.] A plate covering the 

 basal portion of the epistome of 

 certain Arachnids (zool.}. 



prefloration (pre'flora'shun) . [L. 



prae, before ; flos, flower.] The 

 arrangement of floral leaves in a 

 flower-bud (hot.}. 



prefollation (pre'folia'shun) n. [L. 

 prae, before ; folium, leaf.] The 

 arrangement of foliage leaves in 

 the bud stage (hot. ). 



preformatlon theory, the theory of 

 evolution according to which it 

 was supposed that each ovum of 

 an animal contained a miniature 

 adult, and that nourishment only 

 was required to develop it into the 

 perfect form (dial.). 



prefrontal (prefrun'tal) a. [L. prae, 

 before ; frons, forehead.] Appl. a 

 bone anterior to the frontal bone 

 of certain vertebrates ; appl. paired 

 plates or scales anterior to the 

 frontal scale in some Reptiles (zool.}. 



preganglionic (pregang'glion'ik) a. 

 [L. prae, before ; Gk. gangglion, a 

 tumour.] Appl. the (usually) 

 medullated fibres from the spinal 

 cord to the sympathetic cell station 

 (anat.). 



preglobultn (preglSb'ulIn) n. [L. 

 prae, before ; globulus, a small 

 globe.] A compound proteid of 

 white blood corpuscles (phys.}. 



prehallux (prehal'uks) n. [L. prae, 

 before ; hallex, the great toe?] A 

 rudimentary additional digit on the 

 hind limb, in some Amphibia and 

 Mammals (zool.\ 



prehalteres (prehal'tgrez) n. plu. [L. 

 prae, before ; Gk. halter, a weight.] 

 The squamae of Diptera (zool.}. 



prehaustorium (pre'hosto'rium) n. [L. 

 prae, before ; haurire, to drink.] 

 A rudimentary root-like sucker 

 (**). 



prehensile (prehgn'sil) a. [L. pre- 

 Jiendere, to seize.] Adapted for 

 catching hold, as a suctorial 

 tentacle (zool.}. 



prehepatic (pre'he"pat'lk) a. [L. prae, 

 before ; hepar, liver.] Appl. that 

 part of the digestive tract anterior 

 to the liver (emb.\ 



prelacteal (prelak'teal) a. [L. prae, 

 before ; lac, milk.] Pert, a denti- 

 tion which may occur previous to 

 the milk dentition (emb.\ 



prelocallzation (prelo'kaliza'shun) n. 

 [L. prae, before ; locus, place.] 

 The theory that certain portions of 



