GEOBLAST 



514 



GERM 



Geoblast (je' '-o-blast) \yfi, earth ; jUaardg, germ]. In 

 biology, a plumule that in germination rises above the 

 ground, leaving the cotyledons buried, e. g. , that of 

 the pea. 



Geoffroya {je-ojf-roi'-yali) [after Geoffroy, a French 

 physician]. A genus of leguminous trees. G. spin- 

 ulose and G. vermifuga are S. American trees 

 with anthelmintic seeds. Unof. 



Geogenous (je-oj'-en-us) [yrj, earth ; yevi/r, pro- 

 duced]. In biology, applied to such plants as grow 

 on the ground, rather than on other plants ; specifically 

 applied to fungi. 



Geographic Tongue. An eruption on the dorsum of 

 the tongue, which becomes covered with sinuous, map- 

 like lines. It is very chronic and obstinate in its 

 nature, and most frequently attacks young children. 

 It is probably the expression of a tropho-neurosis. 



Geography {je-og' -ra-fe) [/«?, earth ; ypapeiv, to 

 write]. In medicine, a description of the earth's 

 surface with reference to climatology and the distri- 

 bution of disease, with relation to origin and locality. 



Geolin (yX -<?-//;/) \_yf), earth; oleum, oil]. A trade- 

 name for a petrolatum resembling vaselin. 



Geology {je-ol f -o-je) \yfj, earth; Myog, science]. The 

 science treating of the structural development of the 

 earth. 



Geomalism (Je-om'-al-izm) \_}V, earth ; Sjualog, 

 even]. In biology, the tendency of organisms to ad- 

 just themselves to the attraction of gravitation by sym- 

 metric growth in horizontal planes. 



Geomaly ije-om'-al-e). Same as Geomalism. 



Geometry {je-om'-et-re) \yf/, earth ; uerpov, a measure]. 

 That branch of mathematic science that treats of the 

 relations of magnitudes. 



Geophagia (fe-o-fa / -je-ah). See Geophagism. 



Geophagism {je-off'-aj-izni) \yrj, earth ; (payeiv, to eat]. 

 The practice of earth-eating or clay-eating ; chthono- 

 phagia. 



Geophagist (je-off'-aj-ist) [77, earth; Qayeiv, to eat]. 

 A dirt-eater. 



Geophagous (je-off'-ag-us) \yfj, earth ; cjxiyeiv, to 

 eat]. Addicted to dirt-eating. 



Geophagy (je-off'-aj-e). See Geophagism. 



Geophilous (je-off'-il-us) [77, earth; tpi?iog, loving]. 

 In biology, ground-loving, e. g. , certain snails. 



Georgia Bark (jor'-je-ah) [after King George, of 

 England]. The bark of Pinckneya pubens, a tree 

 of N. America ; it is said to be febrifuge. Unof. 



Geotropic (Je-o-trop'-ih) [yrj, earth; rpiizuv, to turn]. 

 Affected by or turning toward the earth ; exhibiting a 

 tendency to grow toward the earth. The roots of 

 plants are geotropic. 



Geotropism (Je-ot'-ro-pizm) \_yrj, the earth ; rpkirtiv, 

 to turn]. In biology, the tendency of roots and other 

 parts to grow downward toward the earth. 



Geotropy (je-ot'-ro-pe). Same as Geotropism. 



Gephyrocercal (jef-ir-o-ser' -kal) [yifvpa, a bridge ; 

 nkpnog, tail]. In biology, applied to fishes in which 

 the aborted tail -fin is replaced by the union of the 

 dorsal and anal fins. 



Geraniin {je-ra'-ne-iri) [yep&viov, geranium]. A pre- 

 cipitate from the tincture of Cranesbill, Geranium 

 maculalum. It stimulates and contracts the caliber 

 of the capillary vessels of the mucous membranes, etc. 

 Dose I to 3 grains. Unof. 



Geranium (Je-ra / -ne-um) [yep&viov, geranium: gen., 

 GeranW]. Cranesbill-root. The root of G. macula- 

 turn, with properties due to tannic and gallic acids. 

 It is useful in diarrhea, infantile colic, etc. G., Ext., 

 Fid. Dose n^v-gj. 



Geratic {jer-at f -ik ) [yijpag, old age]. Relating to old 

 age. 



Geratology (/er-at-ol'-o-je) [yijpag, old age ; Hkyvi*, to 

 speak]. That department of biology that treats of 

 the decadence and gradual extinction of a group of 

 organisms. 



Gerber's Food. A variety of infantile milk-food having 

 the following composition: Water, 6.78; fat, 2.21 ; 

 grape-sugar and milk-sugar, 6.06; cane-sugar, 30.50; 

 starch, 38.48; soluble carbohydrates, 44.76; albumi- 

 noids, 9.56; ash, 1.21. 



Gerdy, Fibers of. See Fibers. G., Ligament of. 

 See Ligament. 



Gerhardt's Sign. See Signs and Symptoms, Table of. 

 G. 's Test. See Tests, Table of. G.', Type Theory 

 of, the molecules were considered as residues that 

 remain unaltered in certain reactions. 



Gerlach's Ammonia-carmine See Stains, Table of. 

 G.'s Carmin Mass, a warm-flowing mass for injecting 

 tissues. Dissolve 5 gm. of carmin in a mixture of 4 c. c. 

 of water and 0.5 c.c. of ammonia. Allow the solution 

 to stand several days, and mix with 8 parts of a solution 

 of gelatin, I to 2. Filter and inject at a temperature 

 of4O C. G.'s Network, or Plexus, an exceedingly 

 delicate fibrous network of the finest nerve-fibrils in 

 the gray matter of the cord. G.'s Theory, pertains 

 to the connection of the nerve-fibers and ganglionic 

 cells of the cord. G. 's Tubal Tonsil, a granular con- 

 dition sometimes noticed at the orifices of the Eusta- 

 chian tubes in chronic inflammations in this region, 

 and due to swelling of the muciparous glands of the 

 tube. G.'s Valve, the fold of mucous membrane that 

 surrounds the mouth of the vermiform appendix. 



Gerlier's Disease. An affection (of farm-hands) charac- 

 terized by sudden paroxysms of ptosis, vertigo, mus- 

 cular paresis, and cervico-occipital pain. See Diseases, 

 Eponymic Table of. 



Germ (jerm) [L., germen, sprig, offshoot, em- 

 bryo]. In biology, (a) a portion of matter potentially 

 vital and having within itself the tendency to assume 

 a definite living form (Harvey) ; a spore, a seed, an 

 embryo, (b) A microbe or bacterium. G.-area, 

 the germinal area, the germinal disc, area germinativa, 

 the spot on an ovum where the development of the 

 embryo begins. G., Asexual, or Unisexual. See 

 Parthenogenesis, Germ-plasm, Evolution, and Repro- 

 duction. G.-band, in embryology, one of the bands 

 that unite to form the primitive streak. G.-cell. I. 

 The germinal vesicle in a non-fertilized ovum. 2. The 

 ovum that has been impregnated, but which is still a 

 single cell ; a cytula, or a blastomere ; a simple sphere. 

 See also Heredity. G., Dentinal, a tooth-papilla, or 

 tooth-pulp. G. of Disease, the special virus or spore 

 through which a disease becomes communicable. G.- 

 disc. See G.-area. G. Epithelium, cylindric cells 

 on the surface of the median plate of the mesoblast. 

 G. -flesh. See Sarcophyte. G. -gland, a germ-produ- 

 cing gland ; an ovary or a testicle. G. -history, ontog- 

 eny, a. v. G. -layer, in biology, any one of the mem- 

 branes of a developing germ , as the blastophylla , epiblast, 

 mesoblast, hypoblast, endoderm, ectoderm, mesoderm, 

 somatopleure, splanchnopleure. G. -plasm, in biology, 

 a term introduced by Weissmann to indicate the repro- 

 ductive or hereditary substance of living organisms. 

 It is held to contain all the primary constituents of the 

 entire organism; it is never produced neogenetically, 

 but is ever passed on from the germ-cell in whicli an 

 organism originates in direct continuity to the germ 

 cells of succeeding generations. It causes the pro- 

 duction of the new individual by directing the pi 

 of division in ontogeny, in the course of which it be- 

 comes changed in a regular manner. It is composed 

 primarily of biophores (a. v.) or bearers of vitality, the 

 smallest units that exhibit vital force. (Cf. pan 



