EXPLANATION OF PLATES 



All figures in the three plates were drawn under a camera lucida at a magnifi- 

 cation of 3000 and reduced one-half in reproduction. 



PLATE 1 



EXPLANATION OF FIGURES 



All drawings made from a smear from a single male of Chorthippus (Steno- 

 bothrus) curtipennis. Vertical columns represent separate cells, each hori- 

 zontal row represents one chromosome in different stages. Figures 1 to 9, at the 

 left, refer to the separate chromosomes arranged in order of size. The letters 

 A to H at the top refer to individual cells, a, Refers to four strand condition, 

 indicating two longitudinal clefts; b, refers to transverse constrictions in the 

 atelomitic chromosomes; c, refers to the chromomere-vesicles. 



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