84 tSe entomologist. 



temperature fluctuated between 20° and 35° C, in such a way 

 that from evening until 10 a.m. the temperature was 20-26° C, 

 but about the middle of the day 25-35° C. All the young larvae 

 now hatched : 5 on Aug. 27th, 20 on the 28th, and 9 up to 

 Aug. 31st. 



On Sept. 12th I removed to Freiburg, and placed the 35 larvae 

 on growing plants of Rumex acetosella in a warmed incubator 

 specially constructed for the purpose, which I call a brood- 

 incubator. The temperature in the same was kept at 27-29° C, 

 and care was taken for the humidity of the air by evaporating 

 water. Pupation likewise took place in the incubator, and I 

 obtained : — 



On Sept. 15th, 1 pupa at 27° C. 



„ 19th, 6 pupae at 27° C. 



„ 20th, 1 pupa at 29° C. 



„ 21st, 6 pup^ at 30° C. 



„ 22nd, 6 pupffi at 30° C. 



„ 23id, 3 pupae at 33° C. 



„ 24th, 2 pupae at 30° C. 



Altogether 25 pupae. 

 These pupae produced 23 butterflies, viz. : — 



On Sept. 19th, 1 butterfly at 27° C. 

 23rd, 1 butterfly at 33° C. 

 25th, 5 butterflies at 24° C. 

 26th, 3 butterflies at 29° C. 

 27th, 5 butterflies at 37° C. 

 28th, 4 butterflies at 37° C. 

 29th, 3 butterflies at 38° C. 

 Oct. 5th, 1 crippled specimen. 



Altogether 23 butterflies. 



The remaining pupae did not emerge, and proved later on to be 

 dried up. One of the butterflies of Sept. 26th escaped. 



It will be noticed that the temperature in the incubator was 

 gradually raised, namely, from 24" C. on Sept. 25th to 38° C. on 

 Sept. 2yth. The pupae of Sicily and Greece aie not often 

 exposed to a higher temperature, as they pupate in shady places 

 on and under stones, &c., where they are not often struck by the 

 rays of the sun. 



Of these 23 butterflies, at least 8 specimens closely resemble 

 the ordinary German phloeas, so that consequently the raised 

 temperature has made no effect upon them. Two specimens can 

 be described as the var. eleiis, as they are as strongly powdered 

 with black, as many specimens of the darkest variety of the 

 butterfly reared at Naples. Both specimens emerged on Sept. 



