46 HYMENOPTERA 



CHAP. 



its work from any suitable plant growing near its nest, and does not 

 confine itself to any particular natural order of plants, or even to 

 those that are indigenous to the South of France. When it has 

 brought a ball of cotton to the nest, the bee spreads out and 

 arranges the material with its front legs and mandibles, and 

 presses it down with its forehead on to the cotton previously 

 deposited ; in this way a tube of cotton is constructed inside the 

 reed ; when withdrawn, the tube proved to be composed of about 

 ten distinct cells arranged in linear fashion, and connected firmly 

 together by means of the outer layer of cotton ; the transverse 

 divisions between the chambers are also formed of cotton, and 

 each chamber is stored with a mixture of honey and pollen. 

 The series of chambers does not extend quite to the end of the 

 reed, and in the unoccupied space the Insect accumulates small 

 stones, little pieces of earth, fragments of wood or other similar 

 small objects, so as to form a sort of barricade in the vestibule, 

 and then closes the tube by a barrier of coarser cotton taken 

 frequently from some other plant, the mullein by preference. 

 This barricade would appear to be an ingenious attempt to keep 

 out parasites, but if so, it is a failure, at any rate as against 

 Lcucospis, which insinuates its eggs through the sides, and 

 frequently destroys to the last one the inhabitants of the 

 fortress. Fabre states that these Anthidium, as well as Meyachile, 

 will continue to construct cells when they have no eggs to place 

 in them ; in such a case it would appear from his remarks that 

 the cells are made in due form and the extremity of the reed 

 closed, but no provisions are stored in the chambers. 



The larva of the Anthidium forms a most singular cocoon. 



o 



We have already noticed the difficulty that arises, in the case 

 of these Hymenopterous larvae shut up in small chambers, as 

 to the disposal of the matters resulting from the incomplete 

 assimilation of the aliment ingested. To allow the once-used 

 food to mingle with that still remaining unconsumed would be 

 not only disagreeable but possibly fatal to the life of the larva. 

 Hence some species retain the whole of the excrement until 

 the food is entirely consumed, it being, according to Adlerz, stored 

 in a special pouch at the end of the stomach ; other Hymen- 

 optera, amongst which we may mention the species of Osmia, 

 place the excreta in a vacant space. The Anthidium adopts, 

 however, a most remarkable system: about the middle of its 



