2 BULLETTX 120, UNITED STATES NATIONAL MUSEUM. 



an unnamed species briefly described by Stevenson (1911), which 

 I am naming Protooj)alina stevensoni. As Cepedea [" Ofdlina "] 

 zdleH is apparently not a valid species, there were 24 recognized 

 species of Opalinidae before the present studies, one of these, 

 Gepcdea{f) [^^ Opalina^^] ;^ar«, being doubtful. 



Since the summer of 1908 the author has been collecting and ob- 

 serving living specimens of American and West Indian Opalinidae 

 and preserved material from all parts of the world. During this 

 period he has been much indebted to many persons for assistance and 

 courtesies in connection with these studies. The Marine Biological 

 Station at Naples preserved and sent intestines of the Mediterranean 

 fish Box hoops, containing Protoop)alina saturnalis in fine condition. 

 Prof. E. A. Andrews, of Johns Hopkins University, sent me im- 

 portant material (adult Bufo marinus and its tadpoles, from Jamaica, 

 and tadpoles from an undetermined Anuran from Bromelia leaf 

 cups in Jamaica). H. H. and C. S. Brimley, of Raleigh, North Caro- 

 lina, collected for me Anura and Urodela. Dr. H. C. Fortner, of the 

 University of Tennessee, sent me Opalinas from Michigan. Prof. 

 E. L. Mark, director of the Bermuda Biological Laboratory, has 

 obtained for me, through his pupil, Mr. C. S. Simkins, important 

 data as to the breeding habits of Bufo marinus in Bermuda, and Dr. 

 Leonhard Stejneger has repeatedly given me assistance in matters 

 of taxonomy of the Amphibia, reviewing my list of names of the 

 forms studied, bringing the nomenclature into harmony with that 

 adopted at the United States National Museum. He has also given 

 considerable zoogeographic data. Professor Hegner kindly sent 

 me an excellent slide of a form collected by Dr. C. E. Simon, which, 

 by permission, I am describing under the tentative name Opalina 

 [larvarum]. With this slide was sent a manuscript copy of a paper 

 (Hegner and Hsiang-Fong Wu, 1921) upon this Opalina. I wish 

 very cordially to thank these authors and Doctor Simon. 



Several institutions have generously extended to me their hos- 

 pitality during periods of work ranging from two weeks to eight 

 months. For this kindness I wish to express my most cordial thanks 

 to the Scripps Institution of Biology and its director, Prof. William 

 E. Ritter; to the University of California and the director of its 

 zoological department, Prof. C. A. Kofoid; to the University of 

 Washington, and to Prof. Trevor Kincaid, director of the Puget 

 Sound Biological Laboratory ; to the authorities of the United States 

 National Museum, and especially to Dr. Leonhard Stejneger, curator 

 of vertebrates in this museum; and to Johns Hopkins University 

 and members of the faculty of its department of zoology. Profs. 

 H. S. Jennings, E. A. Andrews, and S. O. Mast. 



