xxii GLOSSARY OF TECHNICAL TERMS 



EMBRYOLOGY (Gr. fyfipvov, embryo ; Ao'yoj, discourse), the study 



of the development of organisms. 

 EMBRYO-SAC, a chamber in the ovule or immature seed, in which 



the embryo plant begins its development. 

 ENDODERM (Gr. Zvbov, within ; 6e'p/*a, skin), the inner layer of 



cells in a multicellular animal. 

 ENDOPLASM (Gr. tvbov, within ; 7rAao-^a r 4oi'iiLtCtrve material), the 



inner part of the protoplasm in cells. 

 ENDOSARC (Gr. ej;<W, within ; o-ap, flesh), the inner part of the 



protoplasm in Amoeba, &c. 

 ENDOSPERM (Gr. tvbov, within ; o-Trepjua, seed), nutrient substance 



stored within a seed, around the embryo. 

 ENGRAM (Gr. cv, in, upon ; ypajujua, something written or drawn), 



a term used in the mnemic theory of heredity for an 



impression made upon a germ cell and capable of 



giving rise to a corresponding character at some future 



time. 

 ENTELECHY (Gr. eiaeAe'xeia, perfection or total reaction), a kind of 



guiding principle, by which it is attempted to explain life. 

 ENTERON (Gr. Ivrepor, intestines), the digestive cavity in 



embryos and simple animals. 

 ENTOMOPHILOUS (Gr. oro/ios, cut up, = insect ; c/uAos, beloved), 



^tp.rm applied to flowers which are pollinated by insects. 

 ENUCLEATE, deprived of nucleus. 

 EOCENE (Gr. ??w?, dawn; KCU.VOS, recent), the first subdivision of 



the cainozoic period in the earth's history. 

 EPIBLAST (Gr. fat, upon ; /SAaoros, germ), the outer layer of 



cells in the animal embryo. 

 EPICORACOID (Gr. CTTI, upon ; Ko'paf [coracoid] ), one of the bones 



of the shoulder girdle in reptiles, &c. 

 EPIDERMIS (Gr. eTuSe/apu's : fat, upon ; 6ep/xa, skin), the outer layer 



of the skin. 

 EPIGAMIC (Gr. fat, upon; yafxos, marriage), a term applied or 



colouration which serves as a sexual attraction. 

 EPIGENESIS (Gr. fat, upon ; yeVetn?, origin), the theory of 



development by the differentiation of previously undifferen- 



tiated protoplasm ; opposed to " p reformation." 

 EPISEMATIC (Gr. fat, upon; (rij/ua, signal), a term applied to 



colouration which aids in recognition. 

 EPITHELIUM (Gr. fat, upon ; 0r/A??, teat), a layer of cells covering 



a surface. 



