728 GLOSSARY. 



Endoderm. The inner layer of simple organisms. 



Endogenous reproduction. The formation of new cells or organ- 

 isms within the body of the parent individual. 



Endolymph. The liquid contained within the membranous laby- 

 rinth of the ear. 



Endosmosis. The diffusion of a fluid into a vessel through its walls 

 from the exterior. 



Endothelium. The single layer of thin cells which lines the serous 

 cavities, the lymphatic and bloodvessels, and all spaces in the 

 connective tissues (mesoblastic lining cells). 



Epiblast. The uppermost of the three layers of the blastoderm, 

 from which the epidermis and the nerve-centres are developed. 



Epithelium. The non-vascular cellular tissue developed from the 

 epi- and hypoblast of the blastoderm. 



Eupnoea. A term used to denote the normal rhythm of respiratory 

 movements in contradistinction from dyspoena and apncea. 



Excito-motor. Impulses which, reflexly, call forth motion. 



Excito-secretory. Impulses calling forth the activity of gland cells, 

 commonly applied to afferent influences which act reflexly. 



Fibrinogen. A form of globulin obtained from serous fluids, which, 



on being added to a liquid containing serum-globulin, gives rise 



to the formation of fibrin. 

 Fibrinoplastin. A term sometimes applied to paraglobulin or 



serum-globulin. 

 Filiform. A name given to a certain class of the papilla? of the 



tongue, the points of which taper off to a thread. 

 Foetus. The fully-formed embryo while in the uterus or egg. 

 Fungiform. A name given to a certain class of papillae of the 



tongue, which are shaped like a toadstool. 



Galvanometer. An instrument for measuring the direction and 

 strength of electric currents by means of the deflection of a mag- 

 netic needle. 



Ganglion. A swelling. Chiefly used to denote swellings on nerves 

 which contain nerve corpuscles. Hence any group or mass of 

 nerve cells. 



Gastrula. A stage in the development of animals in which they 

 consist of a small sac composed of two layers of cells. 



