402 BIOLOGY 



geotropism (Gr. ge = earth + trope = a turning) . The power possessed 

 by many plants of growing toward or away from the earth. 



germinal. Pertaining to reproduction. 



germ layers. The three layers formed in the developing embryo, 283. 



germ plasm. The substance which bears the hereditary traits and is con- 

 tinuous from generation to generation, 330. 



gills. Thin, expanded organs, bathed in water for respiratory purposes, 

 288. 



gill slits. See branchial openings. 



girdling, 111, 129. 



gizzard. A muscular chamber of the digestive tract where food is ground, 

 158. 



glands. Groups of cells which produce secretions, 167, 176, 204. 



glenoid cavity, 182. 



glomerulus. See Malpighian body. 



glossopharyngeal (Gr. glossa = tongue + pharynx) . A nerve from the 

 brain supplying the tongue and throat, 194. 



glottis. The opening of the trachea or larynx into the mouth, 186. 



glucose. A sugar from fruits, or artificially made from starch, containing 

 maltose and dextrin, 9. 



gluten. 'A proteid from cereals, 8. 



glycerine. One of the decomposition products of fat, 10. 



gonads. Glands producing eggs or sperms, 251. 



Gonium, 240. 



grafting. Inserting a part of one animal or plant into another in such a 

 way that the inserted part retains its life and grows. 



granular. Filled with granules or minute solid particles. 



granular theory of protoplasm, 31. 



gregarious. Congregating. 



growth, 4. 



guard cells, 116. 



gullet. The oesophagus, 158. 



gustatory. Pertaining to taste. 



gynoecium. Same as pistil. 



haemal (Gr. haima = blood). Pertaining to the blood. 



haemoglobin (Gr. haima = blood + Lat. glcbus = globe). A red proteid 

 which colors the blood red, 158, 192, 209. 



hair follicle. The tiny pocket, within which each hair grows. 



hairs, 35, 117. 



hallux. The great toe. 



hand, 365. 



hare, 345. 



