F. M. CAMPBELL-0T7B SOCIAL WASPS. 
157 
does not show the same preference in collecting the raw material. 
The nests can, as regards the outer covering, be divided into two 
classes, the laminar and the cellular. The common wasp and the 
hornet adopt the cellular plan; that is to say, there are in the outer 
covering a number of cavities of the form of a closed tube runniug 
parallel to the axis of the next; while others, like Vespa rufa , 
affect the laminar construction, i.e. the outer covering consists of 
successive layers of paper laid close together and overlapping each 
other. The structure of the nests of the different species varies, 
within certain limits, with the position in which they are placed. 
The hornets make a less complete paper covering to their home, 
according as it is in a hollow of a tree, or in a roof, or under the 
ground, and the same may be said of all the wasps. 
It is impossible to compare the nest of the wasp with that of 
the honey-bee without being struck with the differences that exist. 
The British wasps have no need of such a durable material as wax. 
TJnlike some of their relations abroad they store no honey, if indeed 
anything, nor do the young larvae float in a liquid, as is the case 
with the bee. Except the hybernating females, they live but in 
the season of plenty, and their paper nest is illustrative of their 
ephemeral life. What need have they of a lasting abode? It 
might indeed be expected that a nest made of paper would have 
some characteristics very distinctive from one made of wax, and 
that insects of different habits should prefer different architectural 
arrangements. But who would have thought there would be such 
dissimilarity? The waxen comb of the honey-bee is placed verti¬ 
cally with cells on each side opening horizontally, but the natural 
position of the paper comb of the wasp is horizontal, while the cells 
are only on the lower side, and open downwards. Yet I would 
suggest that the material of the wasp’s nest may account for this 
peculiarity. Let us bear in mind that the paper is made by the 
mastication of vegetable fibres saturated with moisture from the 
mouth of the wasp, and that it is laid on wet. It is evident that 
if, as is the case, the nest were built from above downwards, the 
recently-added portions would not dampen the previous structure, 
for the moisture would pass downwards, as seen in a wet rag or 
piece of paper hung up to dry. The same principle more strongly 
affects the position of the cells. Time is not money in the develop¬ 
ment of a wasp’s nest, but strength. If the community is to be 
flourishing, the population must be large. There must be no delay 
in breeding, and so the eggs must be placed in the cells as soon as 
they are half-built. But damp is an injury to wasps, and especially 
to the larvae. Yet as the cells open downwards the heavy moist 
air caused by their recent construction can escape, and they thus 
dry quickly, as is the case with inverted wet bottles. 
We have thus far traced the history and described the archi¬ 
tecture of a wasp’s nest, and we have now to follow the development 
from the egg to the perfect insect. The royal mother securely 
fastens each egg as it is laid to the side of the cell at an angle of 
about forty-five degrees. The egg is about the twenty-fourth of 
