2 A Third Cooperative Study of " Vespa Vulgaris " 
A point, however, of some interest left unsettled by our earlier papers was the 
influence of winter hibernation on the wing characters of the queens. Is there 
a marked difference between the means, variations and correlations of general 
populations of autumn and spring queens ? We endeavoured to investigate this 
point by collecting queens from nests taken in an adjacent district of the same 
county, Buckinghamshire, during the months of August and September in the 
autumn of 1909. The process was not an easy one as more than 100 nests had to 
be individually taken and a queen extracted. However, we were able to procure 
ultimately 100 queens, and although a few old queens may have by accident been 
included in this number, we have we believe practically a general population of 
queens of the autumn of 1909*. Slides were made of the four wings as in the 
previous cases, and the measurements taken on the right and left front wings. 
We were able to obtain 100 cases of each character measured. This must be 
looked upon as a small sample, but the difficulty of taking the nests without 
injuring the population, and the labour required in making the requisite 1400 
microscopic measurements - ]- really preclude the use of much larger samples. We 
propose, however, in our next wasp study to consider one or two characters only in 
very large samples of queens of the general spring population and of one nest, 
now in our possession. The remarkably small variability of Vespa vulgaris does, 
however, to some extent justify the use of small samples, for it leads to very small 
probable errors in absolute measurements. 
(2) Characters measured. 
These are precisely the same as those of our first and second studies. We 
reproduce the cuts indicating the cells measured. 
We should have wished to some extent to change this series of measurements. 
The two rather unsatisfactory measurements, as greater experience has shown, are 
the maximum breadth D and the length of the cell b, i.e. B. While X (see 
Figs. I and III above) is often a well-marked point, there are cases in which this 
is not so, and the determination of the point Y most distant from X requires some 
care. On the whole, however, the eud of the cell b (see Fig. II) is the most 
troublesome point to determine accurately. Some cases are like Fig. II, but there 
is not infrequently need for very cautious determination of the tangent line with 
the ocular micrometer j. For this reason in the present series a determination 
was, as we have stated above, first made with the ocular micrometer and then 
with a Hilger reading microscope, and any sensible cases of discrepancy between 
* The number of queens in the autumn nests may run from 30 to 100 or 200, and even in special 
cases, as those of two nests of V. germanica sent to us last year, to 500 and over 600 respectively ! 
t The measurements were made in the manner indicated on p. 49 of our second study, but certain 
difficulties having arisen with regard to the maximum breadth D and the length of the cell 6, i.e. B, these 
measurements were repeated with a Hilger reading microscope, and in case of sensible divergence 
between the two methods of measurement the measurement was again carefully examined. 
X A low power is necessary in order to adjust the 'horizontal' line of the micrometer to the length 
of the cell, but this power may leave the eud of the cell b not clearly defined, 
