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THE ENTOMOLOGIST. 



meat, plants kept fresh in water with which acids, alkahes, dye- 

 substances, common salts, Carlsbad salts, — in short, every kind 

 of substance soluble in water, — had been liberally mixed, in- 

 variably produced perfect insects which often enough showed a 

 failure in size or general colouring, but in no case any noteworthy 

 variation in tint or pattern. 



In the above-quoted Eeports of the Caucasian Silkworm- 

 rearing Station at Tiflis (1891—1893), there are many observa- 

 tions on the influence of factors of this nature. According to 

 these, picric acid, eosin, rodin (ammonio-carmine), and indigo 

 are sufficiently assimilated by the larva? of Bumhyx mori, L., to 

 lead to a staining of the silk-fibres. There is no mention in 

 these publications of any effect produced on the corresponding 

 perfect insects. The feeding-experiments were performed in the 

 following manner : twigs of mulberry were steeped in the above- 

 named fluids diluted with water ; they were then rinsed in fresh 

 water and given as food. 



The third point — that of light — may likewise be rapidly 

 passed over with a mere repetition of the statement in my 

 ' Manual,' p. 119. This is as follows : — " Since I was well aware 

 that the development and growth of plants are strongly influenced 

 by differently -coloured rays of light, I had a number of breeding- 

 cages jDrepared, each of which was provided with a differently- 

 coloured pane of glass ; this experiment, however, gave no posi- 

 tive result, although the larvse were exposed to the influence of 

 the coloured light from the time when they were quite small." 

 Further experiments carried on up to the present time seem to 

 me to prove that violet light leads to an acceleration both of 

 larval growth and of pupal development; but there is no evidence 

 of any visible influence of this experiment upon the colouring 

 or marking of the perfect insect (see G. Schoch, Mittheil. d. 

 Schweitz. Entomol. Gesellsch. 1880, p. 540). 



(To be continued.) 



MOTH-ADIPOCERE. 

 By H. Guard Knaggs, M.D., F.L.S. 



In broaching this subject let me premise that, owing to causes 

 which will be explained further on, my experiments in the pro- 

 duction of moth-adipocere have not been so successful as I could 

 have wished ; but nevertheless, and especially taking into con- 

 sideration the fact that a repetition of the experiments would 

 occupy six months, they are sufficiently so to warrant the placing 

 of the following notes before your readers. 



It has often been suggested that moth-grease is of the nature 

 of adipocere, but beyond the fact that both occur after death, 



