GEN- 



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genu (jSn'u) n. [L. genu, knee.] A 

 knee-like bend in an organ or part ; 

 the anterior end of the corpus cal- 

 losum (anat.). 



genus (je'nus) ., genera (jSn'era) plu. 

 [L. genus, race.] A group of closely 

 related species, in classification of 

 plants or animals. 



genys (je'nis) n. [Gk. genys, jaw.] 

 See gonys. 



geobios (je'obl'os) n. [Gk. ge, earth ; 

 bios, life.] Terrestrial life one of 

 Haeckel's terms (dial.}. 



geoblast (je'oblast) n. [Gk.^, earth ; 

 blastos, bud.] A germinating plum- 

 ule of which the cotyledons remain 

 underground (bot.). 



geocarpic (je'okar'pik) a. [Gk. ge, 

 earth ; karpos, fruit.] Having the 

 fruits maturing underground (bot.). 



geology (jeol'ojl) n. [Gk. ge, earth ; 

 logos, discourse.] The science 

 dealing with the structure, activi- 

 ties, and history of the earth. 



geomalism (jeom'alizm) n. [Gk. ge, 

 earth ; omalos, level.] Response 

 to the influence of gravitation (tot.). 



geophilous (jeofilus) a. [Gk. ge, 

 earth ; philein, to love.] Living in 

 or on the earth, the ground. 



geophyte (je'oflt) n. [Gk. ge, earth ; 

 phyton, plant.] A plant which 

 grows in the earth (tot.). 



geotaxis (je'otak'sis) n. [Gk. g*, 

 earth ; taxis, arrangement.] Re- 

 sponse to the laws of gravity. 



geotonus (je'oto'nus) n. [Gk. ge, 

 earth ; tonos, tension.] Normal 

 position in relation to gravity (tot.). 



geotropism (jeot'ropizm) n. [Gk. ge, 

 earth ; trepein, to turn.] Tendency 

 to respond to stimulus of gravity 

 by turning towards it, as the down- 

 ward growth of a root (dot.). 



gephyrocercal (gef'Iroser'kal, jSfi'ro- 

 ser'kal) a. [Gk. gephyra, bridge ; 

 kerkos, tail.] Appl. secondary di- 

 phycercal caudal fin brought about 

 by the reduction of the extreme tip 

 of the heterocercal or homocercal 

 fin (zool.). 



geratology (jer'atol'oji) n. [Gk.geras, 

 old age ; logos, discourse.] Study 

 of the factors of decadence. 



germ (jfirm) n. [L. gennen, bud.] 

 A unicellular micro-organism ; a 

 seed (tot.) ; a developing egg (zool.). 



germ-cell, a reproductive cell, opp. 

 somatic ; a primitive male or female 

 element (btol.). 



germ centre, an area of lymph- 

 corpuscle division in nodules of 

 lymph gland tissue (anat.). 



germ-disc, a small green cellular 

 plate of the germ tube of liverworts 

 (bot.). 



germ layer, an early differentiated 

 layer of cells (emb.). 



germ nucleus, an egg or sperm 

 nucleus (emb.). 



germ plasm, idioplasm ; the physi- 

 cal basis of inheritance. 



germ pore, the exit pore of a germ 

 tube in the spore integument (bot.). 



germ stock, the stolon in certain 

 Tunicates (zool.). 



germ theory, biogenesis ; the theory 

 that living organisms can be pro- 

 duced or developed only from living 

 organisms (btol.). 



germ tube, the short filamentous 

 tube put forth by a germinating 

 spore (bot.). 



germ vitellarium, an organ of 

 Platyhelminths producing both ova 

 and vitelline material. (sool.). 



germ yolk gland,-^-m. some Rhabdo- 

 coels, an embryonic structure con- 

 sisting of the fertile portion of the 

 egg and a sterite\ portion which 

 functions as a yolk gland feeding 

 the fertite ftprlion (zool.). 



germarium (jerma'rium) n. [L. ger- 

 men, bud.] An ovary (zool.). 



germen (jer'men) n. [L. germen, 

 bud.] A mass of undifferentiated 

 cells, the primary form of the germ 

 cells. 



germinal (jer'mmal) a. [L. germen, 

 bud.] Pert, a seed, a germ-cell, or 

 reproduction. 



germinal bands, two sets of rows of 

 cells in early development of 

 Annulates (zool.). 



germinal cells, the cells concerned 

 in reproduction, set apart early in 

 embryonic life (emb.). 



germinal disc, the disc-like area of 

 an egg yolk on which segmentation 

 first appears (emb.). 



germinal epithelium, the layer of 

 columnar epithelial cells covering 

 the stroma of an ovary (emb.). 



germinal layers, the primary layers 



