upon lepidopterous larva, d-c. 311 



tubercles were pure white. Of the three larvae with 

 pink tubercles, one was recognised from its size to be a 

 female, and it was of a dull green colour, with the black 

 markings largely developed. The other two were 

 similarly recognised as males, and they were both of 

 the brightest green colour, but with the black markings 

 well developed (unusually so for so light a ground colour). 

 The perfect insects emerged during the last ten days of 

 April, 1886, and 120 eggs were obtained from the female 

 moth which was developed from the larva with pink 

 spots, the male parent being derived from one of the 

 two pink- spotted larvae just described. The larvae 

 emerged on May 23rd, 1886, and were fed upon haw- 

 thorn. During their first stages they showed a dis- 

 tinctly gregarious habit, and persistently sought the 

 side of their glass cage, which was turned towards the 

 light. Eighty of the larvae were given to me, while the 

 remainder were reared by Dr. Dixey. Of these forty, 

 thirteen were found in the last stage to have yellow or 

 orange tubercles, twenty-seven to have pink spots like 

 the parents. The black segmental rings were not 

 imperfect in any of the forty larvae, as was so often the 

 case in the original batch of larvae. In this they com- 

 pletely resembled their parents. The green ground 

 colour varied, but was mostly bright like that of the 

 male parent. One larva spun a cocoon with apparently 

 no valvular opening. Nearly all the larvae had a 

 diarrhoeal discharge immediately before spinning, but 

 this appeared to be entirely normal, and to be uncon- 

 nected with any unhealthy condition. The eighty larvae 

 given to me were partially used for physiological in- 

 vestigations, but forty-eight became sufficiently advanced 

 in the last stage to note the colours of the tubercles, 

 which were found to be pink in thirty-seven larvae. The 

 results can therefore be tabulated as follows : — 



1885. 80 larvae, of which three (or 3*75 per cent.) 

 possessed pink tubercles. 



1886. 88 larvae, of which 64 (or 72"7 per cent.) 

 possessed pink tubercles. 



It should be added that my larvae were exposed to 

 surroundings of different colours, but that the tubercles 

 and the black markings were entirely unaffected, while 

 the dullness or brightness of the green ground colour 



