156 



ASSOCIATION OF ECONOMIC ENTOMOLOGISTS. 



INDIVIDUAL VARIATION IN ADULTS. 



The color of adults 

 parents and offspring. 



shows considerable variation even between 

 Xine specimens, including the two of the first 

 and seven of the sec- 

 ond generation, vary 

 in ground color of the 

 dorsum from a grayish 

 to a reddish brown, 

 and are marked with 

 varying amounts of 

 black. The variation 

 in the form and size in 

 the same series (see 

 fig. 6) is more strik- 

 ing. The humeral an- 

 gles are more acutely 

 produced in the male 

 parent than in any of 

 the other specimens in 

 the series. The males 

 average smaller and 

 show a greater range 

 of variation in size and 



form than the females. 

 The abundance of food 

 during the nymphal 

 stages is the principal 

 factor which determines the size attained by the adult. Certain 

 measurements have been made of each individual of the nine speci- 

 mens, and are here given in tabular form : 



Fig. 6. — Podisus maculiventris. variation inform, and size of 

 parents and progeny: No. 1, female parent; No. 2, male 

 parent; No. 3, largest specimen of seven of second genera- 

 tion, female ; No. 4, smallest specimen of seven of second 

 generation, male. Enlarged (original). 



Variation in foi 



m and size of 



parents 



and offspring. 











Female parent (No. 1) and female 

 offspring. 



Male parent ( No. 1 ) and male 

 offspring. 





6 



6 



CO 



6 



d 



No. 5. 

 Average. 



© 



SB 



c 



1 



d 



No. 3. 

 No. 4. 

 Average. 



bo 



1 



Length, in millimeters, 

 tip of head to apex of 



12 



5.6 



6.6 

 4 



12 



5.4 



6.2 

 4 



12 



5.4 



6 



4 



12 



5.6 



6.2 



4.2 



12.5 



5.6 



6.4 

 4 



12.1 



5.52 



6.28 

 4.04 



0.5 



.2 



.4 

 .2 



12 



5.5 



7 

 4 



10.5 



5 



5.4 

 3.4 



10.5 



4.8 



5.4 

 3.6 



11 11 



1 5 



Width of body, in milli- 

 meters, from points op- 

 posite anterior margin 

 of scutellum 



Width of body, in milli- 

 meters, from tips of 

 humeral angles 



Length of scutellum, in 



5.1 



5.6 



38 



5.1 



5.85 

 3.75 



.7 



1.6 

 6 











