THE OSMLE 231 



entious housewife, she gives the place a touch of the 

 broom nevertheless. 



Now for the provisions and the partition-walls. Here 

 the order of the work changes according to the diameter 

 of the cylinder. My glass tubes vary greatly in dimen- 

 sions. The largest have an inner width of a dozen milli- 

 meters ; * the narrowest measure six or seven. 2 In the 

 latter, if the bottom suit her, the Osmia sets to work 

 bringing pollen and honey. If the bottom do not suit 

 her, if the sorghum-pith plug with which I have closed 

 the rear-end of the tube be too irregular and badly joined, 

 the Bee coats it with a little mortar. When this small 

 repair is made, the harvesting begins. 



In the wider tubes, the work proceeds quite differently. 

 At the moment when the Osmia disgorges her honey and 

 especially at the moment when, w T ith her hind-tarsi, she 

 rubs the pollen-dust from her ventral brush, she needs a 

 narrow aperture, just big enough to allow of her passage. 

 I imagine that in a straitened gallery the rubbing of her 

 whole body against the sides gives the harvester a sup- 

 port for her brushing- work. In a spacious cylinder this 

 support fails her ; and the Osmia starts with creating one 

 for herself, which she does by narrowing the channel. 

 Whether it be to facilitate the storing of the victuals or 

 for any other reason, the fact remains that the Osmia 

 housed in a wide tube begins with the partitioning. 



Her division is made by a dab of clay placed at right 

 angles to the axis of the cylinder, at a distance from the 



1 Nearly half an inch. — Translator's Note. 



2 About a quarter of an inch. — Translator's Note. 



