( xxviii ) 



cJs are occasionally smaller than the average $. These size 

 differences in the <$ also occur in Xylotrupes. In Phalacro- 

 gnathus mxtelleri, Macleay, we often get the lengthened jaws 

 in the larger ^s, sometimes only in the medium, and never in 

 the small ones. Again, we get nearly black examples in the 

 medium and large $&, but never in the small. Two specimens 

 are forwarded in illustration. 



Nest-building instincts of bees of the genera Osmia 

 and Anthidium. — Prof. Poulton said that he had received 

 from Dr. R. C. L. Perkins the following letter, dated Nov. 15, 

 1915, together with the specimens referred to and exhibited 

 to the meeting : — 



" I am sending a nest of Osmia bicolor, Schk., and two females 

 of the bee. You may like to exhibit it at the Entomological 

 Society and afterwards keep it in the Hope Department. 

 Many years ago my uncle, V. R. Perkins of Wotton-under- 

 Edge, Gloucestershire, described how the $ 0. bicolor, having 

 stored its cells in an empty snail-shell, covers this over with 

 pieces of ' bents ' or dry grass-stems. I have noticed his 

 account quoted in various works. 



" I have myself caught the bees carrying the grass-stems, 

 and found the nests, as he describes. The nest I send was 

 found May 20, 1915, on the edge of a beech- wood near Wotton, 

 and the ground was nearly bare. The snail-shell was in a 

 slight depression, and the material of the nest entirely con- 

 cealed it. This material consists for the most part of the 

 brown scales that drop from the beech-twigs in the spring- 

 time. The bee had practically completed the nest when it 

 was found, but was still fussing about it and tucking in a 

 piece here or there, and now and again bringing a fresh piece. 

 She was very old and worn and had considerable difficulty in 

 flying with a piece of material, owing to the strong breeze, 

 to which the nest was exposed, and her torn wings. This was 

 in the morning. In the afternoon she had disappeared, 

 having, no doubt, quite finished her work. 



" The two bees sent are, therefore, neither of them the 

 maker of this nest ; the one fresh example (dated) was caught 

 on the same day, but the other with the piece of grass-stem, 

 that it was bringing to a nest, at another time. The latter's 



