For a naturalist and limnologist, the Pantanal has the extreme fascination of an "ultima Thule" ofundisturbed and little known wilderness. The scientific world at large is almost unaware of its richness. In an age when scientific research is overstretched because of lack of funds and the hands are full of urgentconservationtasks, it is the amateurtourist who unveils the beauty and the interestof this largest wetland ofthe world. I had the privilege of an outsider, well enough familiarized with Brazil, its language and scientific life, but independent enough of the daily chores of a local academic career. For nearly 20 years I have been a faithful sci- entific tourist to this subcontinent. My academic liberty gave me the unique opportunity to try to synthesize in English the knowledge about Brazilian environments little known abroad. My first suchendeavourhas been"Soore- tama - the Atlantic Rain Forest of Brazil". Dealing now with the Pantanal, I wish to pay tribute to the many Brazilian colleagues who under dire and often precarious conditions have advanced the knowledge related to the Pan- tanal. By reviewing their many reports and papers written in Portuguese and bringing them to the knowledge of the international scientific community, I believe that I am doing a useful service. First of all, I have to thank Prof. Vera Lucia Imperatriz Fonseca, the Head of the Department of General Ecology at the University of Sao Paulo, for providingme during the years, the academic basefrom which I couldoperate.

There are few achievements of modern man which can compare to the Suez Canal. In Egypt-the land of the most famous wonders of antiquity-the Suez Canal was built as the first technical wonder ofthe industrial revolution. Ferdinand de Lesseps was a man straddling two epochs-the romantic utopism of Saint Simon and the modern world of technocracy. The gigantic project was at its start shouldered by the crowds of tens of thousands of forced laborers still available and ended as a show-piece for modern mechanical earth-moving techniques. The canal builders themselves were still polyhistors in the old sense: engineers cum-zoologists; naval officers-cum-geologists; diplomats meddling with chem istry. During the four generations of the existence of the Suez Canal, the fateful professional narrowmindedness became progressively worse. The engineers con tinued their work in and around the Canal, but they became oblivious and unresponsive to the environmental impact, to the fascinating changes in the biotic scenery which they were producing with their own hands."

This book is an attempt to present a comprehensive view on the aquatic biogeog raphy of a small but very dynamic and complex area of the globe. Luckily, this area, called here the Levant, has attracted much interest in the past and is being increasingly studied in the present. The interphasing between the knowledge of the historical and formative processes and that of the recent distributional aspects is fairly good. The recent years saw also a widening effort which expressed itself in several symposia and monographic books. Therefore I considered it possible to treat the whole subject of the aquatic biogeography of the Levant singlehandedly rather than in the presently widespread manner of an edited book. I am keenly conscious of the shortcommings of my approach of presenting much second-hand information. Possibly this is being compensated by the fact that this book has a more coherent structure and eventually a clearer scientific message. The effort spent in synthesizing the data from the widely different sources hopefully pays off in a presentation which is more easily comprehended by the average reader. For the suspicious reader, I would recommend to read first the closing chapter of this book in which the quintescence of this book and its message is presented in a summariz ing manner."

For a naturalist and limnologist, the Pantanal has the extreme fascination of an "ultima Thule" ofundisturbed and little known wilderness. The scientific world at large is almost unaware of its richness. In an age when scientific research is overstretched because of lack of funds and the hands are full of urgentconservationtasks, it is the amateurtourist who unveils the beauty and the interestof this largest wetland ofthe world. I had the privilege of an outsider, well enough familiarized with Brazil, its language and scientific life, but independent enough of the daily chores of a local academic career. For nearly 20 years I have been a faithful sci- entific tourist to this subcontinent. My academic liberty gave me the unique opportunity to try to synthesize in English the knowledge about Brazilian environments little known abroad. My first suchendeavourhas been"Soore- tama - the Atlantic Rain Forest of Brazil". Dealing now with the Pantanal, I wish to pay tribute to the many Brazilian colleagues who under dire and often precarious conditions have advanced the knowledge related to the Pan- tanal. By reviewing their many reports and papers written in Portuguese and bringing them to the knowledge of the international scientific community, I believe that I am doing a useful service. First of all, I have to thank Prof. Vera Lucia Imperatriz Fonseca, the Head of the Department of General Ecology at the University of Sao Paulo, for providingme during the years, the academic basefrom which I couldoperate.