324 THE SCOTTISH NATURALIST 



to ^6' R, and the minimum to 53° F. I am confident that 

 records of the hours of sunshine and of the rainfall, were 

 they available, would much more emphasise the unfavourable 

 conditions of the July period. It is easy to imagine that 

 the weather change would cause an actual slackening of 

 work, and probably also, as the numbers seem to indicate, 

 a check in the hatching of pupae — both of which events would 

 delay the building of comb 5, and therefore the commence- 

 ment of comb 6. 



The very long interval between the building of the first and 

 second combs suggests a remark. It emphasises by contrast 

 the efficiency of the social system in the wasp community; 

 for the 32 days which elapsed before comb 2 was com- 

 menced represent the time taken by a single builder — 

 the queen — in erecting the early portion of comb i. Our 

 numbers indicate that so soon as the workers hatch from this 

 comb (31 da)'s after the first egg is deposited), the 

 building of the second comb is commenced. 



Rates of Egg-laying. — It is very evident that during the 

 period of the nest's growth the rate of deposition of eggs 

 varies greatly. As the rate gradually advances after the 

 workers begin to take their part in cell-building, it will be 

 sufficient to indicate the lowest and highest limits of 

 oviposition as shown by our July nest. 



The slowest period is clearly that during which the queen 

 has not only to stock but has also to build the cells. As our 

 nest offers no evidence on this point which I can regard as 

 unimpeachable, I revert to a nest of another species, examined 

 in another year, as giving an approximation to the general 

 condition. This early nest of a Tree Wasp, Vespa norvegica^ 

 was still being built by the queen alone. It contained a first 

 comb in which were 11 eggs, 18 larvae, and 6 pupae. Now 

 since in 8 days an &%^ hatches, the 11 eggs must have been 

 laid in the course of 8 days, so that the average number laid 



per day was — = 1-375. By similar reasoning, keeping in 



o 



mind that a larva remains as such for 13 days, the 



18 

 ratio — comes to represent the number of larvse hatched 



13 



