Had it some vague consciousness of the services rendered by the elevation of its point of leverage? I cannot believe it, although the beetle profited very cleverly by my platform of little stones, for if the very elementary idea of using a higher base to reach something too elevated was not beyond it, how was it that neither beetle bethought him of offering his back to the other, thus rendering the task possible? One assisting the other, they might have doubled the height attained. They are far indeed from any such combinations. Here, each pushes the ball with all its might, but pushes as if alone, without seeming to suspect the happy result which would be brought about by a combined effort. When the ball is fastened to the ground by a pin, they behave as they would when the ball is stopped by a loop of dandelion, or held by some slender bit of stalk which has got into the soft, rolling mass. My artifice brought about a stoppage not unlike those which occur when the ball is rolling amid the many inequalities of the ground, and the insect acts as it would have acted in some circumstances where I had not interfered. It uses its back as a wedge and lever and pushes with its feet without at all varying its means of action, even when it might call a comrade to its help. If it has to face the difficulties of a ball nailed to the ground with no assistant, its dynamic manœuvres are exactly the same, and it succeeds, so long as we give the indispensable help of a platform gradually built up. Should this help be refused, the Scarabæus, no longer stimulated by the touch of its beloved ball, loses hope, and sooner or later, no doubt with bitter regret, flies off, whither I know not. What I do know is, that it does not return with a squadron of companions whom it has implored to help it. What could it do with them, since it cannot utilise even the single comrade when one shares the ball? Perhaps, however, an experiment which suspends the pellet at a height inaccessible to the insect when its means of action are exhausted may be too much outside of ordinary conditions. Let us try a miniature ditch, deep enough and steep enough to prevent a beetle when placed at the bottom with its load from rolling it up. These are the exact conditions named by Blanchard and Illiger. What happens? When persistent yet fruitless efforts show the beetle that it can do nothing, it spreads its wings and flies off. Long, very long have I waited, on the faith of what these learned men say, expecting it to return with its friends, but I have always waited in vain. Often, too, many days later I have found the ball just where I tried the experiment, either at the top of the pin or at the bottom of the hole, proving that nothing fresh had happened. A pellet abandoned from necessity is abandoned for good and all, without salvage by the help of other beetles. Dexterous use of wedge and lever to move the arrested ball is the highest intellectual effort I have ever seen in the