INTRODUCTION 



To enhance the informational value of the General Embryological Information 

 Service, and to avoid a considerable increase of its size, some changes in the 

 presentation of the data have been made. 



In the Directory of Names and Addresses, which now contains close to 

 3000 names, fewer names without research subjects are listed, as these entries 

 contain incomplete and partially obsolete information (see explanation on p. 7). 

 The number of complete entries has increased by about 10 %. To save space 

 the wording of the research subjects was shortened as much as possible. As in 

 previous volumes the wording used on the data sheets by the investigators 

 themselves was generally retained. Repetitions of words, and parts of entries 

 giving too much detail were omitted; phrases such as: "research on . . ." and 

 "studies of . . ." were cancelled; often methods were put in brackets at the end 

 of the entry. Inevitably these condensations have caused a certain loss of in- 

 formation, but we feel that clarity is not seriously impaired. 



Much attention was devoted to the names of experimental organisms. With 

 only a few exceptions, for the higher animal taxa the following books have 

 been consulted: L. A. Borradaile and F. A. Potts, The Invertebrata (4th ed., 

 1963) and J. Z. Young, The life of vertebrates (2nd ed., 1962). Lord Roth- 

 schild, A classification of living animals (2nd ed., 1965) was also of much use. 



Generally the highest taxon given at the end of the entry is the class, but in 

 Mammalia, Reptilia, Amphibia, and Insecta it is the order, while in Crustacea 

 and Arachnida in addition to the class the name of the order is also given. 



The Book Notices section has ondergone some important changes, which be- 

 came necessary in view of the much greater number of books received. A smaller 

 type was used. New subdivisions into subject categories and types of books 

 were made, and the titles and other bibliographical data are presented in a new 

 format. 



The number of institutes listed has remained fairly constant. No new coun- 

 tries are listed; Jamaica and Zambia no longer appear in the list. 



J. FABER 



B. Z. SALOMfi 



