PREFACE 



This book is but one of several biologies of Crustacea that might 

 be written. The choice of material for inclusion has been a personal 

 one, and has been biased by my own interests. It follows that no 

 attempt has been made to be all embracing. There are, doubtless, 

 many other topics which might justifiably have been included, hut 

 I make no apology for their absence: the space allowed is not 

 unlimited, and the treatment of some topics is already over- 

 condensed. 



While I am not much troubled by what has been omitted, I am 

 deeply conscious of the possibility of error in what has been 

 included; if I have misinterpreted anyone's work I should he 

 grateful for being corrected. 



As a general rule the aim has been to deal with those aspects 

 of biology which concern the whole intact animal. Occasional 

 excursions are made to the interior of the animal, but only in order 

 to explain what is happening to the whole animal. The chapter on 

 blood and circulation is included because the hearts of many 

 crustaceans are visible in the intact animal and can be seen function- 

 ing, likewise the striking changes in the haemoglobin content of 

 Daphnia are easily observed. This chapter owes much to the sus- 

 tained interest aroused when I was privileged to work for several 

 years in the department of Prof. H. Munro Fox. F.R.S.. who has 

 also built up a small but well-selected collection of Crustacea, many 

 of which have been used to prepare the illustrations for this book. 



The selection of references for the literature lists at the end of 

 each chapter has been difficult. In general those selected are fairly 

 recent and in English, and usually easily obtainable, but a few 

 references to the European literature have been included, either 

 because they describe classical work, or else give information which 

 is not yet available in English. Sometimes I have mentioned an 

 author in the text without giving a reference at the end of the 

 chapter: in this case the reference is given in one of the recent 

 papers in the list, and it is usually fairly obvious which one should 

 be consulted. 



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