This interesting book is so packed with information that the effect of reading it at one sitting is a little staggering; it is better to sample individual chapters (any of which can be read separately). Some parts of this book are concerned with animal behviour which is nearly awesome in its curiosity and mystery. In addition to the traditional five senses (and unusual applications of these senses in other animals -- hearing through the skin, echo-sounding, seeing at night) and the kinesthetic sense, the Milnes explore the sense of time, of balance, of direction, and the sense of feel via electric current. One perplexing aspect of the book, however, is that the question of what is to count as a ""sense"" is never discussed. So, although it is intriguing to learn that the female firefly sits on a leaf and waits to see her mate go blinking by (at which point she gives a come hither flash) we are left wondering what the ability and inclination to make winking lights in these circumstances have to do with any sense other than that of sight. The same is true of the fascinating accounts of the honeybee's ability to communicate with its brethren by means of ""dance"" patterns. The authors raise the possibility of inter-species communication in their discussion of animal language.