Isobiochore 



A line drawn on a map connecting regions that possess 

 similar Biological spectra (q. v.). 



Isocies 



A group of Synusiae (q. v.) that show Physiognomic 

 similarity. 



Isoflor 



A line drawn on a map connecting regions possessing an 

 equal number of species within a genus or a family. 



Isogamy 



The production of similar Gametes (q. v.), occurs in 

 certain algae (Ulothrix), fungi, and protozoa, cf. Heterogamy. 



Isogenous 



Refers to organisms that occur in the same region. 



Isogram 



See Isotherm. 



Isohaline 



The line or layer within a body of water which has the 

 same Salinity at a certain time or the same mean salinity 

 over a certain period. 



Isohel 



A line drawn on a map connecting places with equal 

 duration of sunshine. 



Isohyet 



A line drawn on a map connecting places with equal 

 quantity of rainfall. 



Isolation 



The separation of populations from other populations of 

 the same species by geographic, ecologic, climatic, physiolo- 

 gic, or other barriers, cf. Natural selection. 



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