GLOSSARY-INDEX 403 



Haversian canals. The canals in bone in which the blood vessels run. 



heart, 187, 206, 309; of earthworm, 159. 



heliotropism (Gr. helios = the sun -f trope = a turning). The power 



possessed by plants of turning toward the- sun. 

 helotism (Gr. helot = a slave). An association of organisms in which one 



enslaves the other, 228. 



hepatic (Gr. hepar = liver). Pertaining to the liver. 

 hepatic vein. The vein from the liver, 190. 

 herbivorous (Lat. herba = grass + vorare = to eat). Feeding upon grass, 



herbs or other plants. 

 heredity. The appearance in the offspring of characters of the parent, 



326; nucleus in, 48, 259; Weismann's theory of, 329. 



hermaphrodites. Individuals possessing both male and female reproduc- 

 tive glands, 251. 



heterocercal. Applied to a tail-fin with one lobe longer than the other, 

 heterosporous (Gr. heteros = other + spore) . Producing more than one 



kind of spore; i. e., macrospores and microspores, 274. 

 hibernation (Lat. hibernare = to winter). The death-like sleep which some 



animals show in winter, 214. 



high organisms. Organisms with complex structure, 96. 

 hind-brain- The posterior part of the brain, consisting of cerebellum and 



medulla, 193. 

 hind-gut. The hind part of the intestine, the cloacal chamber; also called 



the proctodceum. 

 hinge joint, 185. 

 histology (Gr. histos = a web + logos = discourse). The study of the 



microscopical anatomy of organisms, 19; of earthworm, 166. 

 holophyte (Gr. holos = whole + phyton = a plant). Having the food 



habits of plants, i. e., capable of utilizing sunlight and assimilating 



CO 2 , 221. 

 holozoic (Gr. holos = whole + zoon = animal) . Having the food habits 



of animals, i. e., nourished wholly on organic foods, 221. 

 homocercal. Applied to a tail-fin with both lobes equal. 

 homologous (Gr. homos = like + logos = ratio). Similar in structure, 



364. 

 homosporous (Gr. homos = like + spore). Producing only one kind of 



spore, 274. 

 HOOKER, 38. 

 Horse, foot of, 365. 

 host. A name applied to an animal or plant upon which another is living 



as a parasite, 227. 

 humerus, 182. 



