42 



Marvels of Insect Life. 



post is sufficient, several parallel shafts are constructed. Fabre has shown that 

 if she can obtain a hollow reed of the necessar\^ diameter, she has sufficient of the 

 labour-avoiding spirit to be content with utilizing it. She will also repair nests 

 of previous years to make them serve for her brood. 



It will be evident that the elaboration of these floors from sawxlust, and the 

 gathering of food for each cell must consume some time, so that the larva in 

 the lowest cell must finish its development before the one next above it in this 

 tenement house. If the first fledged bee had to emerge where the mother-bee began 

 her labours, at the top of the shaft, it would have to pierce through all the floors — 

 and incidentally, perhaps, through several of its brothers and sisters — before it could 

 gain its liberty. This is the reason why the carpenter made that lower exit. 

 Each bee-grub at the time it is about to change into a chrysalis fixes itself with its 

 head downwards against the floor of its cell ; and so, naturallv, each new-born bee 

 cuts through the floor and makes its wav through the already vacated cells below. 



But all the grubs of the 

 carpenter bee do not arrive at full 

 development. Some of them fall 

 in the way of parasites, who subsist 

 upon and kill them. In the West 

 Indies one species ^ is victimized 

 by the grub of a rather large beetle, 

 the spotted horia,- which enters 

 the cells and destroys the inmates. 

 One regrets that the big 

 carpenter bee has not crossed the 

 English Channel and added its 

 name to the list of British bees. 

 But if we canviot boast of having 

 one of the largest of bees among our 

 fauna, we have one oi the smallest,^ 

 tliat is also a clever worker in 

 wood, whose metallic blue body only 

 measures a quarter of an inch. It is related, moreover, to the burly continental, and 

 shares its habits, though it works in softer materials as seems fitting to its diminutive 

 size. Ceratina needs no bulky post to accommodate its series of cells. Everybody 

 knows that the long shoots of the bramble that have borne this autumn's crop of black- 

 berries will die off in the winter and bec(jnio bi own and brittle. Next spring ceratina 

 will be taking stock of these, and looking for one tliat has a broken end. Into this she 

 will tunnel, clearing oat the pith to the length ol about a foot, dividing the cleared space 

 into tiny cells, laying an egg in each, and leaving a mass of suitable food. The partitions 

 between the cells arc made of the fragments of i^ith ct'inented together by mc^ans of 

 her saliva. The little white and black osmia'* is aiiolher native carju-nter bee, 

 which drills out the dead bramble-stems, like ceratina, and constructs its crils of 

 the pith, placing them end to end. In this resj^ect it differs from some of its 

 immediate relations, wliich are masons and construct cells of sand and chxy. 



Photo by] 



Spotted Horia. 



[£. St-:p, F.L.S. 



A beetle which in the grub-stage is a parasite in the nest of th" carpenter 

 bee, and destroys the grubs of that Insect. It is a native ot the West 

 Indies; here shown one and a half times life size. 



Xyl<)co]"ia teredi 



- Moiia maculat. 



^ Ceratina c\'anca. 



■' Osmia leiicomclana. 



