Buds and Stipules. By Sir John Lubbock, Bart., M.P. With
340 Illustrations and 4 Coloured Plates. (Regan Paul, Trench, and Co. Gs.)—This is another of those labours of love which have made its author's name famous, and upon the like of which are built the foundations of science. Each man working hard and conscientiously at some single aspect, some tiny question, soon the bearings of the whole mighty problem are revealed. It is often long before the value of fitting and polishing each single piece of the mosaic is recognised, but seldom indeed is careful, painstaking study of any point, however minute, found in the long run to have been thrown away. Just what the ultimate bearing or practical use of this present research upon stipules will be no one can tell as yet, but it is a model of what such work should be. Sir John Lubbock was struck by the fact, some years ago, that the wide variations both in the presence and size of:those tiny leaf-like structures upon each side of the stalks of leaves known as stipules were totally unexplained. To the solution of this problem he accordingly addressed himself, and even if he is not able to wind up his demonstration with an absolutely conclusive Q.E.D., he has accumulated a large amount of interesting in- formation in the process. Stipules he finds to be one of Nature's numerous means of protecting the tender shoot of the coming bud, and their size varies with the amount of protection required and the presence or absence of other envelopes. And the amount of modification which they are capable of undergoing in the dis- charge of their trust is surprising. Some develop a dense woolly coat, and thus form a literal winter overcoat for the shoot; others " waterproof " it by a thick coating of gam-varnish secreted by them. Others of a particularly ingenious turn of mind secrete a sweet juice which attracts ants and wasps, who clear the plant of its vegetarian insect enemies. The well-known spines of the acacia are stipules turned bayonet, while a buckthorn of Southern Europe has beaten its spears, not into pruning, but into climbing, hooks, by winch it scrambles up among other shrubs. But the milord is held by the bull's-horn acacia of the Amazons with a combination a/ ingennities that positively suggest intelligence. Not only do the stipules form large thorns, but these hollow themselves out to form chambers for a garrison of ants, for whom glands at the base of the leaves, and also at their tips, secrete a good supply of honey,--so that it literally hires its protectors by offering meat, drink, and lodging, like a fat burgher-city in the Middle Ages. The same sort of " barracks " have long been noted in the root-mass of certain tree-parasites (orchids) and in bladder-like swellings in the substance of the leaves of two South American Rebiatea. So that Dngald Dalgetty was of most ancient lineage, and could trace his professional pedigree back to the ants. Structures which are so full to bursting of resource and inventiveness certainly deserve a name less deadly dull than stipules?,
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