GLOSSARY 593 



Ebers (a'bers), Georg M. German Egyptologist; 1837-1898. 



ecdysis (ek di' sis). The shedding of the cuticula of an arthropod or of the homy 



scales of a snake or lizard. 

 economic (g k6 n6m' Ik). Pertaining to utilitarian values, either positive or negative. 

 ect- (&kt). G.; without, outside. 

 ectoderm (6k' t6 durm). The outer germ layer in embryogeny; adj., ectodermal 



(6kt6dur'mal). 

 ectoplasm (gk' to plSz'm). The outer part of the cytoplasm of a protozoan; adj., 



ectoplasmic (6k to plSz' mik). 

 effector (6f f6k' ter). A term applied to either a cell or an organ that completes a 



reflex act. 

 efferent (6f' fer 6nt). Outgoing, from a center. 

 egestion (e j6s' chiln). The passing out of feces. 

 egg. An egg cell with its protective coverings. 

 egg cell. The reproductive cell of a female. 

 electrotropism (e l6k trSt' ro piz'm). Response to an electrical stimulus; adj., 



electrotropic (6 l6k tr6 trop' Ik). 

 elimination (e llm i na' shun). The passage out of the body of Hquid waste; adj., 



eliminative (e llm' I na tlv). 

 embryo (6m' bri o). An animal in the early stages of its development; adj., embry- 

 onic (6m brI 6n' Ik). 

 embryogeny (6m brI 6j' e nl). The stages in the embryonic development of an 



animal. 

 Empedocles (6m ped' 6 klez). Greek philosopher; about 500-430 B.C. 

 en- (6n). G.; in. 



encephalon (6n s6f' a I6n). The brain of a vertebrate. 

 encystment (6n slst'm6nt). The formation of a hard covering, or cyst, about an 



organism. 

 endo- (6n' do), or ento- (6n' to). G.; within. 



endocrine (6n' do crin). Pertaining to internal secretions or ductless glands. 

 endomixis (6n do mIk' sis). A process of reorganization of the nuclear material in a 



protozoan cell. 

 endoplasm (6n' do plSz'm). The inner portion of the cytoplasm of a protozoan cell; 



adj., endoplasmic (6n do plftz' mIk). 

 endoskeleton (6n do sk6r e tun). An internal skeleton; adj., endoskeletal. 

 endothelium (6n do the' II lim). An epithelium of mesodermal origin lining coelomic 



cavities, serous spaces, and blood and lymph vessels; adj., endothelial, 

 enteron (6n' ter 6n). A digestive cavity; adj., enteric (6n t6r' Ik). 

 entoderm (6n' to durm). The inner germ layer; also called endoderm; adj. ento- 



dermal (6n t6 dur' mSl). 

 entozoic (6n to zo' Ik). Living within an animal body, 

 enzyme (6n' zim). A catalytic ferment. 

 epi- (6p' I). G. ; upon. 

 epibole (6p lb' 6 le). The growth of a fold of the blastoderm over the surface of the 



embryo, leaving an archenteron between the two. 

 epidermis (6p i dur' mis). The outer epithelial layer of the skin of vertebrates; adj. 



epidermal (6p I dur' mal). 

 epigenesis (6p I j6n' g sis). The conception that the parts of an organism arise from 



an undifferentiated germ cell, in contrast to the idea of preformation. 

 epithelium (6p I the' ll flm). A tissue covering a free surface; adj., epithelial, 

 epizoic (6p I z6' Ik). Living upon the surface of an animal. 

 equatorial (e kwa to' rl al) plate. The group of chromosomes lying in the equatorial 



plane of the spindle in mitosis. 



