690 



GLOSSARY 



for the improvement of the human spe- 

 cies. 



Eu-sta'chi-an tube (named after Enstachi, 

 Italian physician. L. tuba, pipe). A 

 tube leading from the pharynx to the 

 middle ear. 



Eu-then'ics (Gr. eiithenein, to thrive). The 

 science of improving the human race 

 by improving the environment. 



E-vag'i-na"tion (L. e, out; vagina, sheath). 

 An out-pocketing of some part or or- 

 gan. 



E-vis'cer-ate (L. ex, out; viscera, entrails). 

 To remove tlie internal organs. 



Ev'o-lu"tion, organic (L. evolvere, to un- 

 roll; Gr. organon, insti'ument, tool). 

 Descent with modification. 



Ex-cre'tion (L. ex, out; cernere, to sift). 

 Discharge of wastes of metabolism. 



Ex'o-sker'e-ton (Gr. exo, outside; skeJetos, 

 hard). The hardened external struc- 

 ture of animals. 



Ex'pi-ra"tion (L. ex, out; spirare, to 

 breathe). To breathe out. 



Ex-ter'nal res'pi-ra"tion. The exchange of 

 gases between the alveoli of the lungs 

 and the blood. 



Fac'et (L. fades, face). A sub-division of 

 the compound eye in arthropods. 



Fam'i-ly (L. familia, from famulus, serv- 

 ant). The main sub-division of an 

 order. 



Fas'ci-a ( L. a band ) . A sheet of connective 

 tissue which covers and binds parts to- 

 gether. 



Fau'na (L. f annus, a god of the woods). 

 The animal life characteristic of a re- 

 gion. 



Fe'ces or fae'ces (L. faeces, dregs). Undi- 

 gested, unabsorbed food residue. 



Fer'ti-li-za"tion (L. fertilis, from ferre, to 

 bear). The fusion of the sperm with 

 the egg to produce a zygote. 



Fe'tus (L. a bringing forth). The unborn 

 young of any viviparous animal. 



Fi'brin (L. fibra, band). The essential in- 

 soluble protein found in the blood clot. 



Fi-brin'o-gen (L. fihra, band, Gr. gignes- 

 thai, to produce). The soluble protein 

 material which is converted to fibrin 

 during clotting. 



Fis'sion (L. fissus, cleft). Asexual repro- 

 duction in which the cell divides into 

 two parts. 



Fis'sure (L. fissus, cleft). Any groove, fur- 

 row, cleft, or slit. 



Fla-gel'lum ( L. flagellum, whip ) . A mobile, 

 whip-like process. 



Forii-cle (L. folliculus, small sac). A small 

 excretory or secretory sac or gland. 



Fo-ra'men (L. foramen, an opening). A 

 hole in a bone or membrane. 



Fos'sa (L. fossa, ditch). A pit or depression 

 found in bone. 



Fos'sil (L. fossilis, from fodere, to dig). 

 Any naturally preserved record of pre- 

 historic life. 



Func'tion (L. fungi, to perform). Plant or 

 animal action. 



Gam'ete (Gr. gametes, spouse). A mature 



germ cell. 

 Gam'e-to-gen"e-sis (Gr. gametes, spouse; 



genesis, birth). The development of 



gametes. 

 Gan'gli-on (Gr. ganglion, enlargement). A 



mass of nerve cell bodies. 

 Gas'tric (Gr. gaster, belly). Pertaining to 



the stomach. 

 Gas'tro-vas"cu-lar (Gr. gaster, belly; L. 



vasculum, vessel). A cavity used both 



for digestion and circulation. 

 Gas'tru-la (Gr. gaster, belly). The early 



embryonic stage following the blastula 



in which the embryo consists of two 



germ layers. 

 Gas'tru-la"tion (Gr. gaster, belly). The 



process of invagination of the blastula 



to form the gastrula. 

 Gene. Hereditary units located on the chro- 

 mosomes. 



