LYMPHATICS IN FROG LARVAE 83 



APPENDIX 



It is a pleasure to be able to express here something' of my sense of 

 obligation for help received from several individuals and institutions, 

 in the investigations of which this paper presents a major section. 



Grateful appreciation is first due to Prof. Ross G. Harrison, whose 

 suggestion that I work with cardiectomized frog embryos was the 

 starting point for my studies of the lymphatics and blood vessels and 

 their relations in injections of amphibian larvae. 



The present paper could never have been brought to completion 

 under the difficulties imposed on me by ill health while a member of 

 his laboratory, without the constant help and encouragement given 

 by Doctor Harrison personally, and through his laboratory assistants, 

 with ample provision of facilities from the Osborn Zoological Labora- 

 tory of Yale University. 



I must thank members of the technical staff of the laboratory for 

 much help ; especially the secretary, Mrs. Hamilton, and Miss Benedict, 

 assistant in photography and technique. 



My indebtedness to Miss Krause, the distinguished artist of the 

 laboratory, is very great for her fine cooperation in obtaining the 

 necessary understanding of complex structural relations of the injec- 

 tions to make the beautiful and accurate drawings reproduced on the 

 plates. 



Acknowledgments and thanks are due The Wistar Institute of 

 Anatomy and Biology for many facilities during my year of residence, 

 1929-1930; and the continuation of this generous treatment, through 

 the kind interest of the late Dr. H. II. Donaldson, is much appre- 

 ciated, as it has made possible the completion of certain final techni- 

 cal details, with the help of Doctor Farris, Fellow, in charge of 

 operations. 



I am under long standing obligations to the Marine Biological 

 Laboratory, Woods Hole, Massachusetts, for providing me with labora- 

 tory facilities and assistance during a number of summers, while I 

 collected and studied portions of the material on which this paper 

 is based. 



Finally, acknowledgments and thanks are to be recorded for a grant 

 of funds from the Elizabeth Thompson Science Fund, which has been 

 of great assistance. Through this Fund I was able to obtain valuable 

 photographs, which aided greatly in comparing stages and structures 

 in the preparatory period of the work, and was most serviceable later, 

 when it was decided to illustrate through drawings. The drawings 

 here acknowledged as from M. E. Brinton were accordingly provided 

 by the Fund for the set of important stages of the frog's lymphatics. 



