3 28 



KATHARINE FOOT AND E. C. STROBELL. 



Table II. gives the lengths of the intromittent organs from 32 

 specimens of E. ictericus. 



Table III. gives the lengths of the intromittent organs of 71 

 offspring from the back-cross of a pure ictericus male with the 

 one FI female we succeeded in raising from crossing E. vario- 

 larius 9 by E. ictericus cf. 



As the intromittent organ of E. ictericus is much shorter than 



TABLE I. 



Lengths of intromittent organs from 62 

 specimens of Euschistus variolarius 



X 20 diams. 



85.5 mm i 



87 mm i 



88 mm i 



89 mm i 



90 mm i 



91 mm i 



92 mm 2 



93 mm 4 



93.5 mm i 



94 mm 6 



94.5 mm 2 



95 mm i 



95.5 mm 2 



96 mm 7 



96.5 mm i 



97 mm i 



97.5 mm i 



98 mm 6 



98.5 mm i 



99 mm 2 



100 mm 7 



100.5 mm i 



101 mm 4 



102 mm 3 



104 mm i 



104.5 mm 2 



106 mm i 



5,996 mm 62 



TABLE II. 



Lengths of intromittent organs from 32 



specimens of Euschistus ictericus X 



20 diams. 



54.5 mm i 



55 mm i 



58 mm 3 



59 mm i 



60 mm 8 



60.5 mm 3 



61 mm 2 



62 mm 6 



62.5 mm 2 



63 mm 3 



64 mm i 



64.5 mm i 



1,940.5 mm 32 



Mean length = 60.64 mm. 



Mean length = 96.70 mm. 



that of either E. variolarius or E. servus, it was much less diffi- 

 cult to get an accurate measurement of the length of the organ 

 in ictericus and this was true also of the offspring from the 



