MODIFICATION 01^ COLOR. 



i8i 



In these experiments 62 per cent died in the larval stage, 34 per cent in the 

 pupal, and 6 per cent completed their transformations. In the larvse at hatch- 

 ing the dorsal color marks were small, and many were absent ; and in the sec- 

 ond instar all spots had disappeared, excepting the spiracular and wing, and 

 the pronotum and epicranium were light brown in color. The imagines were 

 39 per cent below the normal in size and were equally divided between the 

 sexes. The hypodermal color was white, and there were no dark spots upon 

 the epicranium, nor any upon the pronotum excepting a and c. The elytral 

 stripes were shortened, and the anal, cubital, and costal were wanting. On 

 the ventral surface all spots were obliterated, excepting the anterior sternals 

 upon the thoracic and abdominal segments, and those upon the tarsi of the 

 legs. The general appearance was strongly albinic, as is shown by the 

 following seriation : 



Tabl^ 63. — General color of beetles used. 



Class 



I 



2 



3 



4 



5 



6 



7 



8 



9 



10 



II 



pa. 

 9 



I 



12 



13 



P.ci. 



I 



6 



Parents 



Control ... .. 

 Experiment* . . 



P.ci. 



I 



P.ci. 



7 



P.cL 

 46 



P.ci. 



I 



33 



P.ci. 



I 



I 



22 



P.ci. 



2 



7 

 8 



p.ci. 

 5 

 8 

 2 



P.ci. 

 20 



17 



I 



P.ci. 

 42 

 39 



P.ci. 

 18 

 19 



P.ci. 

 2 



I 



* Number of individuals. 



Empirical mode of parents 9 



Empirical mode of control 9 



Empirical mode in experiment ... 3 



Modal deviation of parents o 



Modal deviation of control o 



Modal deviation in experiment. . — 6 



ExpSrim^nt II. — To determine the effect of a small average decrease in temperature 

 upon the color and color pattern of L. decemlineata when applied throughout life. 



Conditions. — Temperature on the average 6.5° C. below that in nature, 

 with other conditions normal. 



Apparatus. — The same as in experiment 8. 



In this experiment 3,300 freshly laid eggs taken at random were placed in 

 the conditions of the experiment as soon as they were obtained, and from 

 these 2,700 larvse were hatched. The experiments were conducted during 

 the years 1898 to 1904. The temperature records are as follows : 



Tabi,e 64. — Temperature conditions. 



Conditions— 



8 a. m. 



I p. m. 



8 p. ni. 



Maxi- 

 mum. 



Mini- 

 mum. 



Aver- 

 age. 



Deviation 



from 

 normal. 



In nature 



In experiment . 



19 

 16 



° C. 



^' 

 19.48 



° C. 

 21 

 16 



33 



20.5 



13 

 12 



23.66 

 17.16 



°C. 

 



-6.5 



