PLATE 3 
EXPLANATION OF FIGURES 
A; to He, schematic 
A; to A, Illustrating pairing in synapsis and separation at first maturation 
division of homologous chromosomes in Tettigidae. Arrows indicate direction 
of orientation of the chromosomes; lines and dots indicate respectively maternal 
and paternal origin of the pairing chromosomes. 
B, to B; Illustrating manner in which the 23-valent abnormal No. 1 chromo- 
some pairs with and separates from its normal mate; arrows indicate orientation 
of parts. 
C, to D, A supposed method of origin for the 23-valent No. 1. chromosome. 
C, C, Aecidental unequal division in the reduction mitosis, giving a sesqui- 
valent No. 1 chromosome; arrows indicate orientation of parts. 
D, Pairing in synapsis of the sesqui-valent No.1 chromosome of C, with a 
normal No. 1. 
D, Ds Separation in late synapsis. 
D; to D; Imagined revolution of the normal No. 1 about the fragmentary 
end of the sesqui-valent No. 1, giving a 23-valent No. 1 chromosome having the 
two end portions oriented in the same direction. 
D, Carried over whole ina reduction division giving a 23-valent No. 1 chromo- 
some. The distal No. 1 portion corresponds to that part of the long chromo- - 
some in B; to By, which pairs with the normal No. 1. 
FE; to E; Evident method of pairing of the deficient No. 4 of figures 4 to 8. 
Normal No. 4 projects beyond its deficient mate (fig. E2) at its distal end. In 
separation the deficient mate evidently has rotated on the side of this projecting 
end, and has come into position on the metaphase spindle out of line with its 
normal mate; compare figures 5, 6, 7 b, and7 ce. 
F, to F; Showing result expected if in parasynapsis on the pairing of the 
deficient No. 4 with.its normal No. 4 mate there occurred a complete fusion fol- 
lowed by a splitting of the fused body into two symmetrical parts. The chromo- 
somes would be alike in size in the anaphase of reduction (contrary to fact). 
Gi to Gs Showing expected result if the same as above took place in the 
pairing of the 23-valent No. 1 with its normal No. 1 mate. There would be two 
long chromosomes of equal length having clubshaped distal and slender proximal 
ends, the short No. 1 getting a portion of the long No. 1 (contrary to fact). 
H, to He Showing the result if the 24-valent and 1-valent chromosomes 
paired and separated in a plane at right angles to the above split (figs. Gi to Ge), 
the plane of splitting not agreeing with the plane of fusion of the short and long 
chromosome (fig. G2). Two equal chromosomes would result each composed 
similarly of like parts of both (contrary to fact). 
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