8 ACKNOWLEDGME^TTS 



Dr. H. W. Shimer for his assistance with the classification of 

 the Brachiopoda occurring in this region. The Museum of 

 Comparative Zoology, Cambridge, for the loan of books of 

 reference; Dr. A. F. Huettner, of New York University, for 

 his advice and for the plate of Aporrhais ; Dr. W. J. Clench ; 

 Dr. Waldo L. Schmitt, Dr. J. P. Moore, and to Profs. E. B. 

 Wilson, T. H. Morgan, G. N. Calkins, J. H. McGregor, 

 Dr. A. H. Sturtevant, Dr. F. Schrader, and Dr. D. E. Lansfield, 

 for their many kindnesses when I was working in Columbia 

 University. 



In connection with the actual work in the field and labora- 

 tory, I owe much to the great interest taken by Dr. Charles 

 H. Blake, who has been one of the staff of the Survey from 

 the beginning and has been the one to whom all have turned 

 for help of various kinds. In addition to his own work, he 

 has revised and edited the notes on many of the other forms, 

 and what success we have had is due in a great measure to his 

 interest. 



I also wish to express my appreciation of the difficult and 

 exacting work of Dr. S. J. Conrad, of the staff, in developing 

 the technique of the Bryozoa drawings (the drawings speak 

 for themselves), and his interest in making the Survey a 

 success; and to Mrs. E. J. Glidden, who has acted as Secre- 

 tary to the Survey for 3 years, for her painstaking care in 

 the important part of typing and reading the proof. I am 

 deeply grateful to Dr. Raymond C. Osburn, of Ohio State 

 University. Doctor Osburn took all of our material and 

 drawings and wrote the report on the Bryozoa. His kindness 

 made the inclusion of this group possible and the fact that 

 he did it gives the stamp of authority. In his report he thanks 

 Dr. Anna B. Hastings, of the British Museum of Natural His- 

 tory. I wish to add mine for the time and interest shown. I 

 am also glad to express my appreciation of what Miss Rogick 

 did in helping with the drawings. 



