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castes dying. Correct orientation before meta-morphosis is therefore essential for survival inthe worker and drone castes .

The 3 castes are reared in distinctive cells thatwere simulated in the laboratory by gelatincapsules. The end walls of these were modifiedto give various combinations of shape, ventil-ation, and texture. The effect of cell length andgravity was also tested . Artificial capping mater-ials (e .g. paper tissue ("Kleenex"), surgicalgauze, gelatin capsule lids with fine inwardpunctured pin holes, fine mesh plastic screen-ing) were successfully used under both naturaland laboratory conditions .

Larvae of the 3 castes that were spinningcocoons were put in various artificial cells andtheir subsequent behaviour and orientationobserved. The following was concluded :-

(1) Larvae have a sense of orientation soonafter their cells are sealed .

(2) Materials within cells, possible odoursand vibrations outside cells, or possible odoursand glandular secretions in cell end walls in-fluence larval orientation little, if at all .

(3) Larvae orientate correctly in extra longartificial cells (simulating natural ones andhorizontally placed) in which they cannot touchboth ends simultaneously .

(4) In natural cells or cells simulating naturalones, larvae defecate with their anterior endstouching the rough-textured end walls .

(5) Larval orientation is not influenced by cellventilation .

(6) Worker and drone larvae do not orientateto gravity .

(7) Under artificial (and probably natural)conditions, the major factors controlling larvalorientation are:-(a) Worker : primarily texture of cell end walls

(i .e . basal end smooth, capping end rough) andsecondarily shape of cell end walls (i .e . basalend round, capping end flat) .

(b) Drone: texture of cell end walls .(c) Queen : gravity and possibly the rough

texture (i .e. the cocoon of the lower end wall) .(8) Tactile sense organs at the extremities

appear to be involved, and with queens, geotacticsense organs may also play some part . Thisneeds further investigation .

THE ORIENTATION OF HONEYBEES TO THEIR HIVES . By J. B. FREE, Rothanisted Experimental Station,Harpenden .

Honeybees may stray into hives other thantheir own, particularly during their first flightsor when their hives are moved to a new site .This `drifting' behaviour, which is extensivewhen identical hives are arranged in regularformations, is undesirable because it may resultin spread of disease, erroneous selection ofqueens and drones for breeding and lowering ofaverage honey production .

When hives are in rows fewer worker beesdrift from the end than from the centre hivesresulting in the end hives gaining in bees .When hives are in repetitive patterns bees driftmostly to hives occupying similar positions inthe pattern to their own . In some circum-stances more bees drift in one direction than inthe opposite direction . Although individualbees are more likely to drift from small to largecolonies than vice versa the greater numbersflying from the large colonies may result in thesmall gaining numerically .

Drones drift two to three times as much asworkers. More drones and workers from queen-right colonies drift to queenless than to queen-right colonies but drones expelled from queen-right colonies do not drift to queenless ones . The

amount queens drift is unknown .Bees orientate to the colour in the immediate

vicinity of their hive entrance and take little orno notice of the colour of the upper part of theirhive. They learn a colour below their hive en-trance better than one above . They do not learncombinations of colours. They distinguish be-tween some symbols put immediately above thehive entrance . They learn the shape or size oftheir hive and its height above ground . They payparticular attention to the direction their hivefaces. The distinctive odour of a colony does notappear to facilitate orientation of its beesdirectly .

Consequently beekeepers can reduce driftingby : arranging their hives irregularly, facing themin different directions, putting differently col-oured boards immediately above or preferablybelow hive entrances, and having hive stands ofdifferent heights .

REFERENCESFree, J . B . (1958) . The drifting of honey-bees . J . agric .

Sci., 51, 294-306.Free, J . B. & Spencer-Booth, Yvette (1961) . Further

experiments on the drifting of honey-bees . J .agric . Sci., (in press) .