THE GENETICS OF HABROBRACON JUGLANDIS ASHMEAD 



CALCANEA, largest segment of the insect foot, 

 frequently designated the metatarsus. 



CENTROMERE, a definite region of a chromosome 

 which takes the lead in activity during 

 mitosis and meiosis. It is the point of 

 spindle-fiber attachment. 



CHARACTER, a term used to designate any struc- 

 ture, function, or trait of an organism. 

 A Mendelian character represents the end 

 product of development, in which a partic- 

 ular gene has a specific effect. 



CHIASMA, cross-like figure formed by chromatids 

 in meiosis. 



CHORION, tough shell or covering of the insect 

 egg. 



CHROMATID, either one of the two identical 

 strands into which a chromosome splits in 

 anticipation of cell division. 



CHROMOGEN, a substance that under proper condi- 

 tions may give rise to color. 



COINCIDENCE, the ratio of the actual number of 

 double breaks to the expected number of 

 double breaks which should occur if there 

 were no interference. 



COSTA, the first principal insect wing vein. 

 It constitutes the anterior edge of the 

 wing. 



CROSSING-OVER, the interchange of blocks or 

 chains of genes between two homologous 

 chromatids; also applied to characters 

 which show recombination as a result of 

 such exchange. 



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