Sept., 1907 1 Cook: Ix Defense of Incisalia henr.ici. 125 



Point 4. — The alar expanse and the suffusion of the upper surface 

 of the wings are stated (in ^| 4) to afford no diagnostic characters. 



With this I heartily agree ; indeed pointed out the latter fact in 

 the tenth paragraph of my former article (referred to above). What 

 of it? 



Point 5. — In ^ 5 Dr. Skinner characterizes the stigma (which I 

 made the basis of my definition of the species) as " a secondary sexual 

 character that occurs in some males and not in others." In other 

 words, if you mix peas and beans in a bag you will find that the bag 

 contains both peas and beans. " This not only applies to irus-henrici 

 but to some other species in the genus. ' ' We are here considering a 

 concrete case and evidence concerning other species is inadmissible.* 

 Let us avoid side issues. " It has no generic or specific value and is 

 simply an individual variation." This is an opinion and again I 

 would remind the reader that evidence is made up of facts not of 

 opinions. f 



Points. — ^6: On the underside of the primaries the "line 

 running from the costa to the first median nervule . . . has no 

 specific value and no proper correlation with other so-called specific 

 characters given by Mr, Cook" ; and /<?//// 7, ^ 7 : concerning the 

 variable color areas of the secondaries beneath "there is no correlation 

 between any of these characters . . ." 



Very well then, I stand corrected. My generalizations were 

 drawn from such specimens as I possessed and for them held good. 

 My series at the time numbered 63 //ev/r/V/and 106 irns. Every ex- 

 perienced lepidopterist will recognize the difficulties attending an 

 attempt to separate two species which closely resemble each other, by 

 reference to any single feature of the wing ornamentation without 

 considering other features. Especially is this so when one or both 

 of the species is variable. In the present inquiry we have an unusually 



* I would find Dr. Skinner's statement of more value if he had printed the names 

 of some of the Thecla which exhibit this peculiarity. I must profess the ignorance of 

 one whose knowledge is limited and will be grateful for the facts. This is a request 

 for information. 



■f" I will gladly pay five dollars ($5) to anyone who will furnish me with a butter- 

 fly of the male sex, corresponding in essential points with Grote and Robinson's type 

 henrici, which has a stigma. I will pay an equal amount for any male butterfly of 

 the genus Incisalia (Minot) taken in the eastern United States or Canada, without 

 the stigma and which does not agree in essentials with the above named type. This . 

 is not a reward ; the amount offered represents simply the value to me for study of 

 such specimens, if they exist. 



