Among the many wondrous tales that Eisner relates in this memoir of his research on insects is that of a tiny millipede (a polyxenid) that defends itself by coating its attacker--usually an ant--with bristles. Scanning electron micrographs taken by Maria Eisner, co-worker and wife of Thomas Eisner, show how the entangling mechanism works. The bristle tips are grappling hooks that become fastened to the ant's hairs. To make matters worse, barbs on the bristle shafts cross-link the bristles, creating a loose meshwork that muzzles the ant and strings its legs together. After observing an attack, Eisner wrote that the ants "attempted to clean themselves, but in so doing seemed only to aggravate their plight. They wiped antennae with forelegs, drew appendages through the mouthparts, or stroked legs against one another, but they usually succeeded only in further entangling themselves.... Many lost their footing and fell to the side, without ever recovering.... The polyxenids, without exception, survived the encounters."

Unlike the polyxenids, most of the insects Eisner has studied use chemicals to defend themselves. In fact, his discoveries of these defenses, beginning in the 1950s just after he earned his doctorate from Harvard University, helped to found a new field of biology, chemical ecology. He has, ever since, been busy making new discoveries about these surprising strategies in the field and in laboratory experiments at Cornell University, where he is J. G. Schurman Professor of Chemical Ecology. The findings he describes are intriguing--all the more so in that they provide the scaffolding on which we see at work the mind of one of our most distinguished scientists and naturalists.

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