140 THE ENTOMOLOGIST. 
this instance, the cares of the fosterers, if voluntary, were very 
ill repaid. 
The chief matter, however, was the temperature. On first 
examining the nest, I passed my bare arm well down to a con- 
siderable depth, and found the centre of the mass of material so 
warm that I withdrew it hastily, thinking I might have put it in 
the lair of some animal. I do not know what amount of heat 
usually exists in the centre of the wood ants’ nests (as far as I 
have observed, they usually have a temperature raised in some 
degree above the outer air), but in this case the great mass of 
material capable of some degree of fermentation, heaped together 
where it was exposed to strong sunlight and the coincidences of 
thundery weather, would account for the much greater warmth. 
I had not a thermometer with me, but a temperature that feels 
strikingly warm to the arm, itself raised in temperature by much 
exertion, must be considerable, and by such tests as I could apply 
afterwards with a thermometer at hand, I estimated it to be 
about seventy degrees. ‘This was at about two feet beneath the 
surface of the nest, and would give a temperature more than 
twenty degrees above what has been shown here (in the neigh- 
bourhood of Isleworth during April of this year) by earth 
thermometers at one foot and two feet beneath the surface ; or, 
taking one of the warm months of the year as a general guide 
to earth temperatures, about ten to fifteen degrees above the 
amount shown at the same depth during last September. 
The appearance may, of course, have been only coincidental ; 
but still, looking at the unusual amount of protection from 
external chills, and also the unusual amount of internal warmth, 
in connection with the enormous numbers of the Clythra 
where they were usually scarcely represented, it may be worth 
recording. 
With regard to the Rhipiphorus paradoxus, I found this beetle 
present in great numbers early in September, 1870, in a large 
nest of Vespa vulgaris, and being at the time securing all the 
specimens I could meet with for presentation to the Collection of 
Keonomic Entomology then forming at South Kensington, I had 
the opportunity in clearing the combs, cell by cell, of accurately 
observing their contents. The nest was of unusual size and ina 
very dry and warm situation, as well from the general formation 
of the ground as from being in well-kept grass land in the park 
