2, 4-Dichiorophenoxyacetic Acid (2, 4-D) 



A compound used to destroy undesirable plants, applied 

 as a dust or spray to the foliage. 



Dichogamy 



The maturing of stamens and pistils of a flower at dif- 

 ferent times. 



Diclinous (Diclinic) 



Refers to plants that have stamens and pistils in separate 

 flowers, cf. Monoecious, Dioecious, Monoclinous. 



Dicotyledon 



A Vascular plant in the subclass Dicotyledoneae, class 

 Angiospermae (flowering plants), which have seeds contain- 

 ing two seed-leaves or cotyledons, e. g., peas, beans, cf. 

 Monocotyledon. 



Die! 



Refers to the 24-hour period of day and night, cf. Di- 

 urnal, Nocturnal, Crepuscular. 



Differential Species (Differentiating Species) 



A species, because of its greater Fidelity (q. v.) in one 

 kind of community than in other kinds can be used in dis- 

 tinguishing vegetation units. 



Differentiation 



(1) The development of a cell, organ, or immature or- 

 ganism into a mature organism. (2). The development of 

 different kinds of organisms in the course of evolution. 



Digestion 



The conversion of complex, usually insoluble organic 

 substances into simpler and usually soluble compounds by 

 enzymes. 



Dihybrid (Cross) 



An organism resulting from the breeding of parents that 



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