HIL- 



133 



HIS 



was attached to the placenta ; the 

 eye of a seed ; the nucleus of a 

 starch grain (hot.). 



hilus (hl'lCis) ;/. [L. hilum, trifle.] 

 A small notch or opening ; a 

 small opening or depression 

 usually where the blood-vessels, 

 etc., enter (anaf., zool.}. 



hind brain, the rhombencephalon, 

 that portion of the brain derived 

 from the third embryonic vesicle 

 (anaf.). 



hind gut, a diverticulum of the yolk- 

 sac extending into the tail-fold in 

 the human embryo ; the posterior 

 portion of the alimentary tract 

 (anaf.). 



hinge joint, a joint in which the ar- 

 ticulatory surfaces are so moulded 

 to one another as to permit motion 

 in one direction only (anaf.). 



hinge ligament, the tough elastic 

 substance joining the two valves 

 of a bivalve shell (zool.). 



hinge line, the line of articulation 

 of the two valves in a bivalve shell 

 (zool.). 



hinge tooth, one of the projections 

 found on the hinge line in bivalves 

 (zool.). 



hip-joint, the ball-and-socket joint 

 between femur and hip-girdle 

 (anaf.). 



hippocampal (hip'okam'pal) a. [Gk. 

 hippos, horse ; kampos, sea-monster.] 

 Pert, the hippocampus (anaf.). 



hippocampus (hip'okam'pus) n. [Gk. 

 hippos, horse; kampos, sea-monster.] 

 A curved eminence that extends 

 throughout the entire length of the 

 floor of the inferior cornu of the 

 lateral ventricle (anaf.). 



hirsute (heVsut) a. [L. hirsutus, 

 hairy.] Covered with hair-like 

 feathers, appl. birds ; having stiff, 

 hairy bristles (zool.} ; having stiff, 

 hairy covering (hot.}. 



hirudin (hiru'din) n. [L. hirudo, 

 leech.] A substance obtained in 

 solution from the head of leeches 

 which renders drawn blood non- 

 coagulable ; an anticoagulin (phys.). 



hispid (his'pid) a. [L. hispidus, 

 rough.] Having stiff hairs, spines, 

 or bristles (hot., zool.}. 



histoblast (hls'toblast) n. [Gk. histos, 

 tissue ; blastos, bud.] One of the 



units of any tissue (anaf.) ; imaginal 

 discs (zool.}. 



histochemistry (his'tokgm'IstrT) n. 

 [Gk. histos, tissue ; cheinos, juice.] 

 The chemistry of animal tissues 

 (biol.}. 



hlstocyte (his'toslt) n. [Gk. histos, 

 tissue ; kytos, hollow.] A tissue 

 cell as distinguished from a germ 

 cell (zool.}. 



histogenesis (his'tojen'e'sis) n. [Gk. 

 histos, tissue ; gigiiesthai, to pro- 

 duce.] Formation and develop- 

 ment of tissue (biol.). 



histogenic (hls'tqje'n'ik) a. [Gk. 

 histos, tissue ; gignesthai, to pro- 

 duce.] Tissue-producing ; appl. 

 the separate merismatic layers in 

 a stratified growing point (hot.} ; 

 tissue-producing (zool.). 



histohaematin (his'tohe'matin) n. 



gik. histos, tissue ; haima, blood.] 

 ne of the animal pigments with 

 a great affinity for oxygen, and 

 so supposed to be respiratory 

 (Phys.). 



histology (histol'ojl) n. [Gk. histos, 

 tissue ; logos, discourse.] The 

 science which treats of the minute 

 structure of tissues (biol.}. 



histolysis (Mstol'isTs) n. [Gk. histos, 

 tissue ; lyein, to dissolve.] The 

 dissolution of organic tissues 

 (biol.} ; that process by which 

 most of the pupal internal organs 

 dissolve into a creamy fluid, 

 except certain cells round which 

 the new imaginal tissues are 

 formed (zool.}. 



histone (his'ton) n. [Gk. histos, 

 tissue.] An albuminose body de- 

 rived from nucleo-histone (phys.}. 



histophyly (histof'ili) n. [Gk. histos, 

 tissue ; phyle, tribe.] The phylo- 

 genetic history of any group of 

 cells (biol.}. 



histotrophic (his'totrof'lk) a. [Gk. 

 histos, tissue ; trephein, to nourish.] 

 Pert, or connected with tissue 

 formation (phys.). 



histozoic (his'tozo'ik) a. [Gk. histos, 

 tissue ; zoon, animal.] Living 

 within tissues ; appl. trophozoitic 

 stage of certain Sporozoa (zool.}. 



histozyme (his'tozlm) n. [Gk. histos, 

 tissue ; zyme, leaven.] An enzyme 

 found in the kidneys of certain 



