1526 PHILIP p. CALVERT. 



The scope of this Catalogue is set forth on page 266. In defining 

 the major groups and the genera, the endeavor has been to so state 

 their respective characters as to separate them from all other groups 

 of like rank wherever found, and not merely with reference to North 

 American forms. While not as much can be claimed for the specific 

 definitions, yet there, too, a similar attempt has been made ; these 

 throughout have been newly drawn up from specimens, except in 

 the few cases noted in the text where such were not available. Only 

 selected references to previous descriptions of species are given, in 

 view of the existence of the synopses of Dr. Hageu and Mr. Banks. 

 The classification of the Calopteryginse, Agrioninse, Gomphinie and 

 Cordulin?e follows very nearly, although often in reverse order, the 

 latest published views of Baron de Selys, and of the Aeschnin?e, 

 those of Dr. Karsch, while a new arrangement of the Libellulinte 

 has been employed. 



The distribution of each species is given in full, and the informa- 

 tion on this subject will, in many cases, be found to greatly exceed 

 that already published. That it has been possible to do this is owing 

 to the labors of collectors who have submitted their specimens to the 

 writer for examination, and whose results have not, save in two or 

 three cases, been published. Such are the collections made by Miss 

 Mattie Wadsworth, at Manchester, Me. ; Mrs. A. T, Slosson, at Fran- 

 conia, N. H., and in Florida ; Miss A. M. Sharp, in Tama Co., Iowa ; 

 by Messrs. J. P. Moore, at York Harbor, Me., Lake St. Regis, N. Y., 

 and with D. J. Bullock, in the Bahamas ; Prof F. L. Harvey, 

 at Orono, Me. ; W. Sheraton, Pictou, N. S. ; P. C. Truman and E. 

 S. Cheney, S. Dakota ; Prof E. T. Owen, Dane Co., Wis. ; J. F. 

 Schafer, Mt. Pulaski, 111. ; F. S. Jones, Chincoteague and Assateague 

 Is., Va. ; E. V. Beales, Denver, Col. ; G. D. W. Williamson, Dobb's 

 Ferry, N. Y. ; C. C. Adams, Bloomington, 111. ; A. L. Babcock, 

 Sherborn, Mass. ; T. D. A. Cockerell, Las Cruces. N. Mex. ; A. 

 Davidson, M.D., Los Angeles, Calif ; W. D. Richardson, Freder- 

 icksburg, Va. ; H. L. Walker, Belvidere, 111. ; G. Miller, York, Pa. ; 

 Prof 0. B. Johnson, Seattle, Wash. ; F. H. Hillman, Reno, Nev. ; 

 W. J. Fox, Jamaica ; E. F. Hitchings, Worcester, Mass. ; C W. 

 Johnson, Dover, N. J., and Great Wicomico River, Va. ; Michigan 

 and Colorado Agricultural Colleges ; and by the writer in the White 

 Mts., N. H., Saratoga, N, Y., and Sea Isle, N. J. 



From time to time the writer has been requested to name such 

 books as would serve as introductions to the study of this group of 



