TWENTY-THIRD ANNUAL REPORT 79 



tion of dry plates and developing papers. And, moreover, cellu- 

 loid coated with the same emulsion as glass has decidedly more 

 speed. 



The films are unbreakable, and their weight is a mere trifle 

 compared with the same number of glass negatives, and halation 

 is practically eliminated. 



The finished film negatives can be filed in an extremely small 

 space such as a filing cabinet used for letters, and in case of 

 necessity one man alone could easily carry from a building a num- 

 ber of these negatives which represented in the same number 

 by the old glass negatives would require at least ten men to 

 transport. In other words, the films require one-sixth of the 

 storage space and are one-tenth of the weight. This is a tremen- 

 dous advantage both to the explorer, and the commercial pho- 

 tograher. 



Bulletin. — Six numbers of the Bulletin were issued in 1918, 

 and despite the continued scarcity of sources upon which to draw 

 for contributions the standard of the publication was thoroughly 

 maintained. "The Quest of the Okapi," by Herbert Lang, illus- 

 trated by the author's beautiful photographs, and an article on 

 the "Mammals of Australia," by W. H. D. Le Souef, were the 

 most noteworthy contributions. Mr. Beebe furnished several 

 stories from his apparently inexhaustible fund of material, and 

 Mr. Crandall and Mr. Ditmais with their usual skill and perse- 

 verance turned old stories into new ones. And, Dr. Hornaday's 

 genius for unearthing editorials where no editorials seemed to 

 exist has added just the necessary finish to the editorial depart- 

 ment. Dr. Townsend and the Aquarium staff supplied the mate- 

 rial for two of the six numbers of the Bulletins. 



Annual Report. — The report for the last year was issued 

 as heretofore. 



Zoopathologica. — Dr. George A. MacCallum continued his 

 writing for this publication, furnishing a paper of sixty pages, 

 divided into three numbers, illustrated with many drawings, on 

 the genus Telorchis, studies of the Polystomidea and notes on 

 the genus Camallanus. 



Zoologica. — Two numbers are in the hands of the printer; 

 one by W. H. D. Le Souef, and the other devoted to the work 

 of Mr. Beebe at the Tropical Research Station in British Guiana. 



