106 INSECT ARCHITECTURE. 



it where none of those trees, nor any other of the 

 same description, grew. His bees also refused to 

 make use of bitumen, and other resinous substances, 

 with whicli he supplied them, though Mr Knight, as 

 we shall afterwards see, was more successful.* 



Long before the time of Rt aumur, however, Mouf- 

 fet, in his Insecfarum Thcafrinn, quotes Cordus for 

 the opinion, that propolis is collected from tlie buds 

 of trees, such as the poplar and birch; and Reim 

 says it is collected fi-om the pine and fir.t Huber 

 at length set the question at rest; and his experi- 

 ments and observations are so interesting, that we 

 shall give them m his own words: — 



" For many years," says he, " I had fruitlessly en- 

 deavoured to find them on trees producing an ana- 

 logous substance, though multitudes had been seen 

 returning laden with it. 



" In July, some branches of the Avild poplar, Avhich 

 had been cut since spring, with very large buds, full 

 of a reddish, viscous, odoriferous matter, were brought 

 to me, and I planted them in vessels before hives, in 

 the way of the bees going out to forage, so that they 

 could not be insensible of their presence. Within a 

 quarter of an hour, they were visited by a bee, which 

 separatmg the sheath of a bud with its teeth, drew 

 out threads of the viscous substance, and lodged a 

 pellet of it in one of the baskets of its limbs: from 

 another bud it collected another pellet for the oppo- 

 site limb, and departed to the hive. A second bee 

 took the place of the former in a few minutes, fol- 

 lowing the same procedure. Young shoots of poplar, 

 recently cut, did not seem to attract these insects, as 

 their viscous matter had less consistence than (ho 

 former. J 



* Phil. Trans, for 1807, p. 212. 



t Sohirach, Hist, des Abeilles, p. 211. 



t Kirby and Spcncc observed bees very bu^y in rolled iii;^ 



