674 



COLLEGE ZOOLOGY 



Gullet (L. gula, gullet). Synonym for esoph- 

 agus. 



Gy-nan'dro-morph (Or. gyne, woman; aner, 

 man; morphe, form). An individual showing 

 a condition where part of an animal may be 

 male and another part female. This should 

 not be confused with hermaphroditism, 

 which is concerned chiefly with the repro- 

 ductive organs. 



Hab'i-tat (L. habitare, to dwell). The environ- 

 ment in which an animal lives. 



Hap'loid (Or. haploos, single; eidos, form). 

 The reduced or halved number of chromo- 

 somes typically found in a mature gamete; 

 half the diploid number of chromosomes. 



Hav-er'sian ca-nal (After Havers, an English 

 physician. L. canalis, water pipe). One of 

 the canals of the bone that permits the pas- 

 sage of blood vessels and nerves. 



He'li-ot'ro-pism (Or. helios, sun; trepein, to 

 turn). See Phototropism. 



He'mal ( Or. haima, blood ) . Referring to the 

 blood or blood-vascular system. 



He'mo-coel (Or. haima, blood; koilos, hollow). 

 A portion of the body cavity functioning as 

 a part of the circulatory system, as in the 

 arthropods. 



He'mo-glo"bin (Or. haima, blood; L. globus, 

 globe) . The pigment in red corpuscles of the 

 vertebrate capable of carrying oxygen; in 

 invertebrates, it is usually in the plasma. 



He'mo-phir'i-a (Gr. haima, blood; phil, to 

 love). An abnormal condition in man in 

 which there is a delayed clotting of the 

 blood. It is an inherited condition. 



He-pat'ic (Gr. hepar, liver). Pertaining to the 

 liver. 



Her-biv'o-rous (L. herba, herb; vorare., to de- 

 vour). Feeding chiefly on plants. 



Her-ed'i-ty (L. hereditas, heirship). The study 

 of the transmission, from parents to off- 

 spring, of developmental potentialities 

 (genes) and how they come to expression. 



Her-maph'ro-dite (Gr. Hermes; Aphrodite). 

 An individual possessing both male and fe- 

 male reproductive organs. 



Het'er-o-cer"cal (Gr. heteros, other; kerkos, 

 tail). Pertaining to the type of tail which is 

 asymmetrical internally as well as externally. 

 Examples: the shark and sturgeon tails. 



Het'er-on"o-mous (Gr. heteros, other; nomos, 



law) . The condition in which the metameres 

 of an animal are not similar; metameres spe- 

 cialized in various parts of the body. 



Het'er-o-z/'gote (Gr. heteros, different; zeu- 

 gon, yolk). An individual having two mem- 

 bers of an allelic pair of genes dissimilar; for 

 example Bb, which has unlike genes as a re- 

 sult of mutation and therefore produces 

 gametes of two kinds with respect to such a 

 gene. The unlike genes may be any two of 

 an allelic series. Compare with Homozygote. 



Hi'ber-na"tion (L. hiems, winter). The pass- 

 ing of the winter in a dormant inactive state. 



His'ta-mine. A powerful dilator of the capil- 

 laries; it is found in all animal and plant 

 tissues. 



His'to-gen"e-sis (Gr. histos, tissue; gignesthai, 

 to be born). The origin, development, and 

 differentiation of the tissues of an organism. 



His-toro-gy (Gr. histos, tissue; logos, study). 

 That branch of anatomy which deals with 

 the miscroscopic structure of tissues and 

 organs. 



Horo-blas"tic egg (Gr. holos, whole; blastos, 

 germ ) . An egg that divides completely into 

 cells during cleavage. 



Horo-phyfic (Gr. holos, whole; phyton, 

 plant). A tv'pe of nutrition found in green 

 plants and in some flagellates, which involves 

 photosynthesis. 



Horo-zo"ic (Gr. holos, whole; zoion, animal). 

 A type of nutrition, found in most animals, 

 that involves ingestion and digestion of or- 

 ganic material. 



Ho'mo-cer'cal (Gr. homos, same; kerkos, tail). 

 Pertaining to the t}'pe of tail which is ex- 

 ternally symmetrical but internally asym- 

 metrical. 



Ho-moro-gous chro'mo-somes (Gr. homos, 

 one and the same. Gr. chroma, color; soma, 

 body). Chromosomes carrying genes affect- 

 ing the same traits; one is paternal and the 

 other maternal in origin. They come to- 

 gether in synapsis. Thus the individual is, 

 genetically speaking, double in composition. 



Ho-moro-gy (Gr. homos, same; logos, study). 

 Basic similarity; structural likeness of an 

 organ or part of one kind of animal with 

 the comparable unit in another, resulting 

 from descent from a common ancestry. 

 These organs may or may not have the same 

 function. 



