280 HABITATIONS OF INSECTS. 



cells, particularly their interior surface: their edges become thicker, and 

 they have acquired a consistence, which at first they did not possess. The 

 combs, also, when finished are heavier than the unfinished ones ; these 

 last are broken by the slightest touch, whereas the former will bend sooner 

 than break. Their orifices also have something adhesive, and they melt 

 less readily ; whence it is evident that the finished combs contain something 

 not present in the unfinished ones. In examining the orifice of the yellow 

 cells, their contour appeared to the younger Huber to be besmeared with 

 a reddish varnish, unctuous, strong-scented, and similar to, if not the same 

 as, propolis. Sometimes there were red threads in the interior, which were 

 also applied round the sides, rhombs, or trapeziums. This solder, as it 

 may be called, placed at the point of contact of the different parts, and at 

 the summit of the angles formed by their meeting, seemed to give solidity 

 to the cells, round the axis of the longest of which there were sometimes 

 one or two red zones. From subsequent experiments, M. Huber ascer- 

 tained that this substance was actually propolis, collected from the buds of 

 the poplar. He saw them with the mandibles draw a thread from the 

 mass of propolis that was most conveniently situated, and, breaking it by a 

 sudden jerk of the head, take it with the claws of their fore-legs, and then, 

 entering the cell, place it at the angles and sides, &c., which they had pre- 

 viously planished. The yellow colour, however, is not given by the pro- 

 polis, and it is not certain to what it is owing. The bees sometimes mix 

 wax and propolis and make an amalgam, known to the ancients and called 

 by them mitys and pissoceros, which they use in rebuilding cells that have 

 been destroyed, in order to strengthen and support the edifice. 1 



We know but little of the proceedings of the species of bees not indi- 

 genous to Europe, which live in societies and construct combs like that 

 cultivated by us. A traveller in Brazil mentions one there which builds 

 a kind of natural hive : " On an excursion towards Upper Tapagippe," 

 says he, " and skirting the dreary woods which extend to the interior, I 

 observed the trees more loaded with bees' nests than even in the neigh- 

 bourhood of Porto Seguro. They consist of a ponderous shell of clay, 

 cemented similarly to martins' nests, swelling from high trees about a foot 

 thick, and forming an oval mass full two feet in diameter. When broken, 

 the wax is arranged as in our hives, and the honey abundant." 2 



Humble-bees are the only tribe besides the hive-bee, that in this part of 

 the world construct nests by the united labour of the society. The habita- 

 tions composing them are of a rude construction, and the streets are ar- 

 ranged with little architectural regularity. The number of inhabitants, too, 

 is small, rarely exceeding two or three hundred, and often not more than 

 twenty. The nests of some species, as ofBombus* lapidarius, terrestris, &c., 

 are found under-ground, at the depth of a foot or more below the surface ; but 

 as the internal structure of these does not essentially differ from that of 

 the more singular habitations of B. muscorum, and as some of the subter- 

 ranean species occasionally adopt the same situation, I shall confine my 

 description to the latter. 



1 Nouvelles Observations sur les Abeilles, par Frai^ois Huber, ii. 101 288. I 

 have observed the bees collecting propolis in the spring from the buds of Populus 

 balsamifera. 



2 Lindley in R. Military Chronicle, March 1815, 449. 



3 Apis. * *. e. 2. K. 



