56 THEODORE H. PRISON. 



requirements of the nesting instincts which are so pronounced in 

 bumblebee queens looking for a place to adopt as their home. 

 Further, I could purchase very cheaply all the material that I 

 needed for making these artificial nests. As a saver of time the 

 artificial nest was a great improvement over anything I had 

 ever used before. The nests could be made up at any time of 

 the year, in any number and during odd moments. Formerly, I 

 had to look for grass suitable for my purpose in spring, the very 

 busiest time of the year for one attempting a biological study of 

 bumblebees. 



A slight variation of this artificial nest was often used. It 

 consisted essentially of dividing the box into two sections, by 

 means of a wooden partition. One of these sections was then 

 made into an artificial nest as described above and a hole made 

 in the partition so that the bumblebees could go from one section 

 to the other. The remaining section was then used solely as a 

 feeding chamber. 



The liquid food which must be supplied to a queen bumblebee 

 in confinement was kept in a small tin container. In the un- 

 partitioned box this container was placed in one corner, and in 

 the divided type in the section adjacent to the artificial nest. 

 The liquid food supplied to the confined queens was simply pure, 

 strained honeybee honey diluted with water. A mixture of 

 sugar and water is eagerly consumed by hungry queens, but does 

 not compare for this purpose with diluted honey, principally 

 because it is not so concentrated. Adult bumblebees as well 

 as the larvae feed on pollen, but sometimes in confinement the 

 queens can not be induced to eat the honeybee pollen. To 

 defeat this indisposition on the part of the queens to feed on 

 pollen, I occasionally added a small amount of rye flour to the 

 diluted honey. In this way I hoped the queens would get some 

 of the rye flour when lapping up the honey mixture. Pollen is 

 rich in nitrogen and when eaten by the queens in spring probably 

 contributes to the development of the eggs, causing the queen to 

 become "broody" and finally to seek a home. Rye flour is 

 also rich in nitrogen, and hence might aid in bringing about the 

 same effect. The receptacles for the liquid food should permit 

 as little exposure of the liquid as possible. Bumblebee queens 



