44 



INSECTS. 



Their cells are built in rows in the solid wood of trees, and the method of procedure 

 will be observed in the illustration exhibiting the violet carpenter-bee (X. violacea). 

 This species, which is rare in Northern Europe, forms a series of cells in each of 



which lies a larva, and since the lower 

 ones are obviously the oldest, it is some- 

 what difficult to understand how the newly - 

 -emerged perfect bee escapes into the upper 

 air from the lower cell. At present it is 

 not altogether clear what course it takes ; 

 whether it gnaws its way through the 

 chambers where brothers and sisters are 

 peacefully awaiting future developments 

 at the imminent risk of arresting all 

 chances of such by thus breaking into their 

 bedrooms, to the detriment of nervous 

 systems not yet hardened to bear the strain 

 or whether it gnaws its way straight 

 out at the side, seems a matter of doubt. 

 Some authorities state that the female has 

 already foreseen and guarded against such 



VIOLET-WINGED CARPENTEIl-BEE, WITH CELLS CUT OUT I'll L' 1. 



IN A TREE-STEM. undesirable contingencies, by preparing a 



door of escape at the bottom of the lower 



cell. And they record as a remarkable fact that the bees, each in turn, gnaw 

 through the floor of its cell, and of course find their elder brother or sister already 

 flown from the cell next below. They never go in the opposite direction through 



1, 2, HAIRY-LEGGED FLOWER-BEE (Anthophora hirsuta], female and male , 3, 4, TUFTED FLOWER-BEE (A. 

 retusa), female and male; 5, WALL-NESTING FLOWER-BEE (A. parietina), female; 6, 7, LONG-HORNED BEE (Eucera 

 lonyicornis), female and male. (All of nat. size.) 



the roof. Our next examples of this family are the flower-bees (Anthophora), of 

 which three species are shown in the annexed illustration. In general appearance 

 these insects closely approximate to humble - bees. They build their nests in 



