20 INTRODUCTORY LETTER. 



desired, and to their courtesy and uniform kindness much of the success of 

 the natural history operations is attributable. 



In the special work of preparing- the reports relative to its collections, 

 the expedition is under obligations to a number of distinguished scientists 

 for their kind and gratuitous services in the work of identification of the 

 individual specimens. The following are among the large number of the 

 gentlemen in question: 



In the determination of — 



INSECTS. 



( 'oleoptera, Mr. Henry Ulke, of Washington, I). C. ; Dr. George H. 

 Horn, of the Academy of Natural Sciences of Philadelphia; Prof. John L. 

 LeConte, of the Academy of Natural Sciences of Philadelphia. 



Lepidoptera, Mr. W. H. Edwards, of Coalburgh, W. Va.; Mr. Theo. L. 

 Mead, of Cornell University, New York; Mr. E. II. Stretch, of San Fran- 

 cisco, Cal. 



Orthoptera, Prof. Cyrus Thomas, of Washington, D. C; Mr. S. H. 

 Scndder, of Cambridge, Mass.; Prof. Townend Glover, of the Agricultural 

 Department, Washington, D. G; Mr. Charles II. Dodge, Agricultural 

 Department, Washington, D. C. 



Hymenoptera, Prof. E. T. Cresson, of the American Entomological 

 Society ; Dr. A. S. Packard, jr., of the Essex Institute, Salem, Mass. ; and 

 Mr. Edward Norton. 



Diptera, Baron C. R. Osten-Sacken, of the Museum of Comparative 

 Zoology, Cambridge, Mass. 



Hemiptera, Dr. P. R. Uhler, of the Peabody Institute, Baltimore, Md. 



Spiders, Dr. William Holden, of Columbus, Ohio. 



Neuroptcra, Dr. II. A. Hagen, of the Museum of Comparative Zoology, 

 Cambridge, Mass. 



Leeches, Worms, Crustacea, and Larvce, Prof. A. E. Verrill, of Yale Col- 

 lege, New Haven, ( !onn.; Prof. J. Leidy, of the University of Pennsylvania; 

 Dr. H. A. Hagen. 



