96 PROCEEDINGS OF THE ACADEMY OF [Feb., 



Derotmema laticinctum (p. 389). 



Based on thirty males and twenty-eight females from five localities. 



Single type here designated: 23 cf ; Mesilla, New Mexico, June 

 30, [1897]; A. P. Morse; Scudder Collection. 



Derotmema delicatulum (p. 390). 



Based on five males and three females from three localities. 



Single type here designated: d* ; Lancaster, California, July 31, 

 [1897]; A. P. Morse; Scudder Collection. 



Derotmema saussureanum (p. 391). 



Based on forty-five males and thirty-four females from eight 

 localities. 



Single type here designated: d\; San Bernardino, California, 

 July 16, [1897]; A. P. Morse; the type specimen has blue wings. 

 Scudder Collection. 



Derotmema lentiginosum (p. 393). 



Based on ten males and two females from two localities. 



Single type here designated: cf ; South Park, Colorado, August 

 11-16, [1877], [Altitude 8,000-10,000 feet]; (S. H. Scudder); Scudder 

 Collection. 



Derotmema lichenosum (p. 394). 



Based on forty males and fourteen females from ten localities. 



Single type here designated: cf ; Alkali [Stage Station, Green 

 River], Wyoming, July 27, [1877], [elevation 6,000 feet]; (S. H. 

 Scudder); Scudder Collection. 



SECTION TWO. 



In this section of the series of Single Type papers it has been 

 decided to treat the North American species which have been de- 

 scribed by the authors. -It has seemed best to consider these all in 

 one paper, not making divisions of the different papers in which the 

 new species were described, owing to the frequent brevity and con- 

 siderable number of such papers. In the present paper we have 

 few of the difficulties to contend with which we encountered and dis- 

 cussed in Section One of this series of articles, because it has always 

 been the custom of the authors to describe new species from one 

 specimen, if but one sex of a new species was at hand, and from two 



23 There is no male specimen in the typical series from Las Cruces, New 

 Mexico, the first locality given in the original description. 



