I place upon the honey-paste a Mason-bee's egg which I myself saw laid in an adjacent cell. The Bee picks it out and throws it away at a distance, as she did with the straws just now. There are two inferences to be drawn from this, both extremely interesting. In the first place, that precious egg, for whose future the Bee labours so indefatigably, becomes a valueless, cumbersome, hateful thing when it belongs to another. Her own egg is everything; the egg of her next door neighbour is nothing. It is flung on the dust-heap like any bit of rubbish. The individual, so zealous on behalf of her family, displays an abominable indifference for the rest of her kind. Each one for himself. In the second place, I ask myself, without as yet being able to find an answer to my question, how certain parasites go to work to give their larva the benefit of the provisions accumulated by the Mason-bee. If they decide to lay their egg on the victuals in the open cell, the Bee, when she sees it, will not fail to cast it out; if they decide to lay after the owner, they cannot do so, for she blocks up the door as soon as her laying is done. This curious problem must be reserved for future investigation. (Cf. "The Life of the Fly": chapters 2 to 4; also later chapters in the present volume.--Translator's Note.) Lastly, I stick into the paste a bit of straw nearly an inch long and standing well out above the rim of the cell. The insect extracts it by dint of great efforts, dragging it away from one side; or else, with the help of its wings, it drags it from above. It darts away with the honey-smeared straw and gets rid of it at a distance, after flying over the plane-tree. This is where things begin to get complicated. I have said that, when the time comes for laying, the Mason-bee arrives with a pellet of mortar wherewith immediately to make a door to the house. The insect, with its front legs resting on the rim, inserts its abdomen in the cell; it has the mortar ready in its mouth. Having laid the egg, it comes out and turns round to block the door. I wave it away for a second, at the same time planting my straw as before, a straw sticking out nearly a centimetre. (.39 inch.--Translator's Note.) What will the Bee do? Will she, who is scrupulous in ridding the home of the least mote of dust, extract this beam, which would certainly prove the larva's undoing by interfering with its growth? She could, for just now we saw her drag out and throw away, at a distance, a similar beam. She could and she doesn't. She closes the cell, cements the lid, seals up the straw in the thickness of the mortar. More journeys are taken, not a few, in search of the cement required to strengthen the cover. Each time, the mason applies the material with the most minute care, while giving the straw not a thought. In this way, I obtain, one after the other, eight closed cells whose lids are surmounted by my mast, a bit of protruding straw. What evidence of obtuse intelligence!