The Osmiae 



millimetres;^ the narrowest measure six or 

 seven. - 



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 mor- 

 tar. 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 mo- 

 ment when, with 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 strait- 

 ened 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 



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

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



73 



