Ill 



"Notes on the Nest of Bombus Derhamellus. 



" On the 2ud of August, whilst walking at the side of a wood at Hampstead, my 

 attention was attracted by a male humble-bee which was skimming over a bank. It 

 suddenly alighted and disappeared : on examining the spot where I lost sight of it, I 

 found a track of moss, about nine inches long ; this was the covered way to the nest, 

 which, together with its contents, I carefully secured for examination. The species 

 was Bombus Derhamellus. The nest was about eight inches long and six broad. At 

 this period of the year the labours of tbe community were over ; with tbe exception of 

 about half a dozen females, all tbe bees had quitted the cocoons ; in six cells I found 

 a small portion of honey. The total number of cocoons was 187 ; judging from the 

 differences in the sizes of these, I consider 107 as being those of workers, 44 those of 

 males, and 36 those of females. In the nest I found thirteen females (six others were 

 subsequently developed), fourteen males and two workers. The mass of comb was of 

 an irregular form, the cocoons being spun one over the other, that is to say, the fe- 

 males had spun a layer of cocoons on the top of some of those of the workers, those of 

 the males being intermixed with them. Reaumur says the pupa is placed with its 

 head downwards, and makes its way out at the bottom of the cocoon ; in my nest the 

 case was exactly the reverse. The females were all in fresh and beautiful condition, 

 the mother bee, or founder, having probably perished some time previously, when the 

 process of depositing her eggs was completed. 



" The nest swarmed with the Acarus with which humble-bees are so much infest- 

 ed ; the larvae of Volucella borabylans were also very numerous, and in all stages of 

 growth, and I reared two or three perfect insects from them. I also found the larva?, 

 pupa?, and perfect insects of Cryptophagus Lycoperdi in considerable numbers. The 

 larvie of a Tinea (T. Sarcitella) were also very numerous; from these I obtained the 

 perfect insect. I also found three or four specimens of Antherophagus glaber. 



" The immature larva? of Volucella were plentiful, but on what they would feed I 

 cannot determine, there being neither larva? nor pupae remaining. I observed them 

 to frequent those cells which contained honey, and I think, notwithstanding they are 

 said to be insectivorous, that they feed also on the honey and wax: on the latter, the 

 Acari undoubtedly partly subsist. The larva of Tinea Sarcitella feeds on the cocoons 

 themselves : a number of these moths appeared in a perfect state at intervals, and I 

 observed the larva? in the empty cocoons of the bees in all stages of growth. The 

 larva? of Cryptophagus I found also in the honey and wax ; when full fed, they bury 

 themselves in the ground, and soon appear in the perfect state. 



" Since writing the above notes, I have received a letter from Mr. Walcott, of 

 Bristol, a gentleman who has made the bees a particular study, and is well acquainted 

 with the genus Bombus. He says, ' In the last week in August, I found a nest of 

 Bombus Derhamellus on our Downs ; it was at least a hundred and fifty strong. In 

 watching the nest, the males re-entered it with the neuters ; but, I should observe, that 

 the females had not appeared, this strengthens what I have lately supposed, that the 

 males continue to re-enter the nest until the females are out, after which they forsake 

 the nest. The bees invariably make their exit from the top of the cocoon ; their mode 

 of proceeding is this : a note or hum being heard from the encased bees, both males 

 and neuters hasten in a body, clustering themselves as close as possible on and about 

 the cell, either to soften the wax on the cocoon, or to give encouragement to the en- 

 cased bee to make the great effort of delivering itself; and immediately on the bee 

 making its exit from the cell, it hastens to the old cocoons containing honey to feed, 



