Mar.,i9o9.J OSBURN : OdONATA BlOLOGIA CeNTRALI-AMERICANA. 41 



considers the enormous amount of material from this region, nearly 

 11,000 specimens, which has been in Dr. Calvert's hands. As we 

 should expect, these new species occur most frequently among the 

 smaller Zygoptera, the genus Argia containing the surprisingly large 

 number 22 (as against 26 species previously known). The presence 

 of such an array of the smaller, more inconspicuous species is due not 

 only to the very careful analysis of the material, but it is in a good 

 measure traceable to the recent collecting trips of a number of ex- 

 perienced odonatologists (besides Calvert himself) into this region. 

 The collections and notes made by these gentlemen, fully accredited 

 in the work, have added largely in many ways to the value of the 

 paper. 



This work of Calvert's stands alone in American odonatology. 

 The only paper of sufficient scope to be in any way comparable is 

 Hagen's Synopsis of N. A. Neuroptera (1861) and that was pioneer 

 work. But for that matter there are few works in the whole field of 

 systematic entomology which can be compared with this when we 

 consider the amount of material studied as well as the thoroughness, 

 care and painstaking effort with which all the details of the material 

 have been searched and weighed. It is a model of modern syste- 

 matic entomology and the reviewer heartily recommends to all stu- 

 dents of systematics a careful consideration of the methods employed 

 by Calvert in the pursuit of this work.* The elimination of " snap " 

 judgment, and even to a great degree, of the personal equation, by 

 long series of measurements in the study of genera, species and 

 variations, may not appeal strongly to some entomologists, but it is 

 scientific and assures a safe basis for permanence of results. 



PROCEEDINGS OF THE NEW YORK ENTOMO- 

 LOGICAL SOCIETY. 



Meeting of October 6, 1908. 



Held at the American Museum of Natural History, President C. W. Leng pre- 

 siding, with eleven members and three visitors present. 



The librarian, Mr. Schaeffer, reported the receipt of the following exchanges 

 since May, 1908. 



Bull. 46 and 48, University of Montana. 



Mittheil. a. d. Zool. Mus. in Berlin, IH, No. 4 ; IV, No. i. 



The Polymorphism of Ants, by W. M. Wheeler. 



* See " Science," Nov. 13, 1908, for Calvert's own account of his methods. 



