190 NORTH AMERICAN MUTILLIDAE 



They show no trace of the inferior incision which is supposed to 

 separate them from, certain other genera. 



f). Compare the wings of several specimens of imperialis and 

 of pluto (type of Neophotopsis). The former is supposed to have 

 two, the latter only one, recurrent vein, that being the method 

 of distinguishing between the two genera. In imperialis the 

 second recurrent vein is represented by a very faint color mark, 

 sometimes perceptible with difficulty and for only part of its 

 length. In pluto it is usuall}^ less distinct, but sometimes faintly 

 indicated. Is it an acceptable character for separating genera 

 and groups of genera? 



The following table will illustrate the classification of the 

 Mutillidae, albeit a tentative one, used in the present series of 

 papers. 



