596 GLOSSARY 



habitat (hab' I tat). The area in which a species of animal or a group of animals 



lives. 

 Haeckel (h6k' 61), Ernst H. German biologist; 1834-1919. 

 haplo (hap' 16). G.; simple. 



haploid (hap' loid). The reduced number of chromosomes. 

 Harvey, William. English anatomist and physician; 1578-1657. 

 head. An anterior region of the body containing the dominant part of the nervous 



system and the chief sense organs. 

 Helmholtz, von, Hermann L. F. German physicist; 1821-1894. 

 hem, haem (hem). G.; blood, 

 hemi- (hgm' 1). G.; half. 



hemocoel (he' m6 sel). Coelom-like spaces devoted to the circulation of the blood. 

 hemoglobin (he mo glo' bin). A protein found in the blood which by combining with 



oxygen increases the amount of the gas which can be distributed over the body, 

 hemolysis (h6 mbl' I sis). Solution of the red blood corpuscles. 

 hepatic (he pat' Ik). Pertaining to the liver, 

 herbivorous (her blv' 6 rtis). Plant-eating; a plant-eating animal is known as a 



herbivore (htir' bl vor). 

 hermaphrodite (her maf r6 dit). An animal containing both male and female 



gonads; adj., hermaphroditic (her maf ro dIt' Ik). 

 Herodotus (he r6d' 6 ttis). Greek historian; 484?-425 b. c. 

 hetero (hgf er 6). G.; other, different. 

 heteronomous (h6t er 6n' 6 mtis) metamerism. A type of metamerism involving 



unlike metameres. 

 heterosis (h6t er 5' sis). Increased vigor due to hybridity. 

 heterozygote (h6t er 6 zi' got). An organism in which two corresponding genes or 



characters are unlike; adj., heterozygous, 

 hibernation (hi bur na' shun). Dormancy during winter. 

 Hippocrates (hi p6k' ra tez). Greek physician; 460-377 b. c. 

 holo (h6l' 6). G.; whole, 

 holoblastic (h6l o bias' tik). A term applied to egg cells possessing total cleavage, 



involving the whole cell. 

 holophytic (h6l 6 fit' Ik). Plantlike as to type of nutrition, involving the utilization of 



inorganic substances and the carrying on of photosynthesis. 

 holozoic (h6l 6 zo' Ik). Animal-like as to type of nutrition, involving the ingestion 



of organic food, 

 hom (hom). G.; the same. 



homolecithal (ho mo 16s' I thai). A term applied to an egg cell with the yolk uni- 

 formly distributed. 

 homology (h6m6r6jl). Structural similarity due to common origin, both evolu- 

 tionary and embryonic; adj., homologous (ho m6l' 6 gus). 

 homonomous (h6 m6n' 6 mus) metamerism. A type of metamerism involving like 



metameres. 

 homozygote (ho m6 zl' gSt). An organism in which the corresponding genes or 



characters are alike; adj., homozygous. 

 Hooke, Robert. English mathematician and microscopist; 1635-1703. 

 hormone (hor'mon). An internal secretion which, carried by the blood from the 



organ which produces it, influences other organs or growth processes, 

 host. An organism that harbors a parasite. 

 Huxley, Thomas H. English biologist; 1825-1895. 



hybrid (hi' brid). The offspring of parents differing in species or in genetic con- 

 stitution; the production of such is hybridization. 

 hydr (hi' d'r). G.; water. 



