Appendix 829 



Elemental theory, the entire individual is explained as a result of the summation 

 of the activities and characteristics of its ultimate parts (contrast with 

 Organismal theory). 



Elytra (el' i tra) (Gr. elytron, sheath), sheathlike wings of beetles. 



Embryo (em' brio) (Gr. embryon, embryo), early stages of development of an 

 organism. 



Embryology (em bri -ol' o ji) (Gr. embryon, embryo; logos, study), study of early 

 development of organisms. 



Embryonic disc (embryonic shield), a cellular partition separating the amniotic 

 and yolk sac cavities of certain embryos from which the embryo proper 

 will form. 



Embryophyta (em bri -of i ta) (Gr. embryon, embryo; phyta, plants), plants pro- 

 ducing a multicellular embryo. 



Emulsion (e-mul'shun) (L. emulgere, to milk out), mixture of two liquids or 

 semisolids, neither of which is soluble in the other, with the result that one 

 is in the form of droplets suspended in the other. 



Emulsoid, a suspension of the nature of an emulsion but with the dispersed phase 

 more finely divided. Cream is a system of fat droplets suspended in water. 



Encystment (en -sist' ment) (Gr. en, in; kystis, sac), surrounded by a protective 

 coat. 



Endocardium (en do kar' di um) (Gr. endon, within; kardium, heart), inner lin- 

 ing of the heart. 



Endocrine (ductless) glands (en'dokrin) (Gr. endon, within; krinein, to sepa- 

 rate), ductless glands which produce internal secretions from materials 

 brought to them by blood and whose secretions are carried from them by 

 the blood. 



Endoderm, see Entoderm. 



Endometrium (en do -me' tri um) (Gr. endon, within; mefra, womb), a heavy, 

 mucous glandular layer of the uterus during pregnancy. 



Endoparasite (en do -par' a sit) (Gr. endon, within; para, beside; sitos, food), an 

 internal parasite (lives within body of its host). 



Endoplasm (en' do plazm) (Gr. endon, within; plasma, liquid), inner cytoplasm of 

 a cell. 



Endopodite (en -dop' o dit) (Gr. endon, within; pons, appendage), inner of two 

 branches of a biramous appendage of a crustacean, 



Endoskeleton, internal skeleton. 



Endosperm (en'dospurm) (Gr. endon, within; sperma, seed), nutritive substances 

 within the seed coats but not a part of the embryo proper. 



Endosteum (en -dos' te um) (Gr. endon, within; osteon, bone), internal lining of a 

 bone. 



Endothelium (en -do -the' li um) (Gr. endon, within; thele, nipple), cells arising 

 from mesoderm and lining blood vessels and lymph spaces. 



Enteric (en-ter'ik) (Gr. enteron, intestine), pertaining to digestion or digestive 

 tract. 



Entoderm (en'todurm) (Gr. entos, within; derma, skin), inner germ layer (con- 

 trast with ectoderm). 



Entomology (en to -mol' o ji) (Gr. entomon, insect; logos, study), science dealing 

 with insects. 



