Ej, Eg, Eg. — First, second and third generations following 



irradiation with X-rays. 

 Ecad. — A plant type which has resulted from adaptation to 



the selective effect of environment. 

 Eccyesis. — Extra-uterine growth of the foetus {e.g. in a 



Fallopian tube) ; ectopic gestation. 

 Ecobiotic Adaptation. — Adaptation to a particular mode of 



life within a habitat (Huxley). 

 Ecoclimatic Adaptation. — Adaptation to the broad physical 



and climatic features of any particular region. 

 Ecoclines. — The graduations of variation produced within a 



species by its reaction to the different ecological zones in 



which it occurs, cj. Cline and Geocline. 

 Ecogeographical Divergence. — The evolution from a single 



ancestral form of two or more different forms each in a 



different geographical area and each adapted to the local 



peculiarities of its particular area. 

 Ecological Divergence. — Adaptation to different ecological 



conditions resulting in the evolution of divergent types. Eco- 

 logical divergence includes ecobiotic adaptation, ecoclimatic 



adaptation, ecogeographical adaptation (or divergence) and 



ecotopic adaptation, q.v. 

 Ecological Isolation. — Separation of groups due to change 



in habit or habitat (especially of insects changing their food 



habits and thus becoming isolated from the rest of the species). 

 Ecological Rules. — See under Allen, Bergmann, Gloger, 



Rensch. 

 Ecology. — The relationship between living organisms and 



their environment. 

 Ecophene. — Ecad, q.v. 

 Ecophenotype. — A habitat form. 

 Ecoproterandry. — The maturing of male flowers before the 



female flowers. 

 Ecoproterogyny. — The maturing of female flowers before 



the male flowers. 



