scales overlap, a purplish color appears (iridescence), whereas 

 when seen in the opposite direction these scales appear black; 

 and in a few of the females the large ocelli of the hindwings 

 had the centerfield purple in color as seen from all angles ; 

 however, not one was obtained with an appendix or enlarge- 

 ment of the ocelli of the forewings in this brood, as occurred 

 in our other, former experiments. The butterflies from the 

 100 caterpillars from the same mother, however, raised and 

 developed in a normal summer temperature were like the 

 mother in size and color, and we did use this lot of butterfles 

 for further experiments. 



Our other line of experiments with Junonia, from which 

 we now have the thirty-fifth generation, were never crossed 

 with any other from outside, but always inbread ; it is re- 

 markable that we. by doing so, could keep the size of the 

 butterflies the same. As we had now in this new line ex- 

 ceptionally large males as well as females, we wished to im- 

 prove the size still more; so we divided all the fertile females 

 into two lots, and intended to cross them in each generation 

 in the following simple manner: We will name one lot (a), 

 the other (b), when we take in each following generation the 

 males from lot (a) and pair these with the females out of lot 

 (b), and the males out of lot (b) paired with females out of 

 lot (a), we could not fail to get the blood mixed. We got 

 plenty of eggs from different females of the first generation ■ 

 bred in humidity, and we kept these separate in two lots, each 

 of 100 caterpillars, raised these in about 80°-90° and humid 

 air, as in the first generation from which we obtained the 

 large butterflies; we provided the caterpillars with the very 

 best food; however, in this high temperature and humidity 

 some of the caterpillars got the wilt disease, and some when 

 still quite small will get lost or killed in changing the food. 

 This generation we bred a full cycle, from the egg to the 

 butterfly, in the short time of one month ; whereas this butter- 

 fly in our normal summer temperature makes usually only 

 two generations in the summer season; and in the winter 

 season remain mostly as chrysalides. 



Our average temperature for hatching the eggs and rais- 

 ing the caterpillars was about 80°, and for the chrvsalides 90° ; 

 we had for these experiments no self-regulating incubator, so 

 the temperature was not always the same, and we here take 

 from the notes which were written regularly three times each 

 day, the average temperature. W^e have found in former ex- 

 periments by breeding the chrysalides in a small self-regulat- 

 ing incubator that the butterfly shows no marked dift'erence 

 in color and markings, whether always bred in 80° or in 90°- 

 95° temperature, only the time of emergence of the imago be- 

 comes shorter as the temperature becomes higher; when, 

 however, these chrysalides are exposed for a long time, un- 



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