STUDIES ON CHROMOSOMES 89 
y Me 
Q 
J /y\\\ : 858 8%» 
fay ts 
@ Y 
/. X 
p e%@ Gi 10 ge 
Ct see ag ree 
. | a 0 Oe sa ae 
oe oe 
& WW x 2 
as I : ae 
Fig.5 Comparison of the XY-group in various Hemiptera. (a~ are orig- 
inal; the others from Payne.) a, 6, Thyanta custator, ‘A form,’ second division 
in side view; c, d, corresponding views of the ‘B form’; e-h, anaphases of same; 
i, polar view of first division of same; j, k, metaphase chromosomes, second divi- 
sion, Diplocodus exsanguis; 7, similar view of Rocconota annulicornis; m, similar 
view of Conorhinus sanguisugus; , Sinea diadema; 0, Prionidus cristatus; p, 
Gelastocoris oculatus; g, anaphase chromosomes of the same species; 7, the XY- 
group, from the second division, Achollamultispinosa; s, diagram, slightly modified 
from Payne, to show the distribution of the XY-components in the second divi- 
sion of the same species. 
JOURNAL OF MORPHOLOGY, VOL. 22, NO. 1 
