62 rULVJXAUTA YITIS, YAH. BIBESIJL 



branch of the food-plant was glistening white with 

 their ovisacs. 



With regard to the males, I noted one remarkable 

 fact they were almost exclusively confined to those 

 branches which harboured the old dead females and 

 their ovisacs of the previous year ; only a very few male 

 puparia occurred upon branches which had not been 

 previously tenanted by the females. The wood which 

 was tenanted by the previous generation was older, 

 and there was naturally less space upon it for their 

 successors ; but whether this fact, together with the 

 greatly overcrowded condition of the individuals, had 

 any effect upon the production of males, I am unable 

 to say, but, taking all the facts into consideration, is it 

 not probable that it had ? In the numerous colonies of 

 this species which have come under my observation, I 

 only once previously met with the male puparia, and 

 that was under precisely similar conditions. The plant 

 had become overcrowded, and the male puparia were 

 fixed chiefly on the old wood among the dead females 

 of the preceding generation. 



Honey-deu'. The greatest amount of this secretion 

 was expelled towards the end of April and onwards ; 

 and, from what I could gather by experiment, between 

 the hours of 8.30 a.m. and 10 a.m., and again between 

 4 p.m. and 6 p.m., but the process continued through- 

 out the day, as well as during the night. By fixing a 

 piece of grease-proof paper beneath a branch occupied 

 by 100 females, I was able to ascertain exactly how 

 many drops of secretion were expelled at any time of 

 the day during fine weather, and also the distance to 

 which it was ejected. On one occasion I found that 

 the 100 females had expelled 225 drops between 

 8.30 a.m. and 10 a.m., and 97 drops between 5 p.m. 

 and 5.30 p.m. on the same day. Judging from 

 repeated experiments, I estimate that the 100 females, 

 during a day of twelve hours (6 a.m. to 6 p.m.), expelled 

 about 800 drops of secretion, which is equal to eight 

 drops per insect per day. These figures do not include 



