THE YOUNG NATURALIST. 



The Determination of Species of Lepidoptera by 

 examination of their Anal Appendages. 



* By F. N. PIERCE. 



I have read with much interest, Mr. C. A. Briggs' article on my 

 paper, and feel complimented with the remarks on my patience, &c. 

 No doubt to sift this matter to the bottom requires a deal of time and 

 trouble, but my idea was not the identification of individual speci- 

 mens of lepidoptera by these means, but the determination of species 

 in this order. Fortunately for many entomologists, the markings on 

 the wings are quite sufficient, as a rule, to identify specimens. 



Mr. Briggs speaks of the plan being practically useless as regards 

 the ZygcenidcB, but a species is not generally composed of a single 

 specimen ; if every variety is to be considered a species, until proved 

 to the contrary, we should soon be in a mess. In fact, I question 

 very much if unique specimens are often distinct species. 



With regard to Mr. Briggs' queries. If I understand the first 

 question rightly, he wishes to know if there is any difference in the 

 organs of fresh dead and dried specimens ? None. 



If any difference could be caused by pairing ? I will answer this 

 more fully afterwards. I have tried captured males, generally worn, 

 and therefore likely to have paired, and also bred specimens, that had 

 not paired, but there is no difference. 



Whether all the specimens were of the same age, and that all had 

 or had not paired ? I understood it was generally accepted that 

 insects did not grow after the final transformation, therefore, I should 

 think it was impossible for organs to develop with age. A plate 

 would answer this better than pages of words. Had I been able to 

 draw, figures of the parts would have appeared with my article, un- 

 fortunately, I am not gifted like the author of " Wings " ; but I will 

 see if something cannot be done by photography to supply this defect. 



I cannot see how pairing can alter structure. If Mr. Briggs is 

 taking the plates of Dr. Buchanan White and others as examples of 

 my work, he is making a mistake, as they are based on totally dif- 

 ferent principles. If an organ is not dentated before pairing it is 

 obviously impossible that any such change in its structure can arise 

 after the act of impregnation. If one of the appendages has two 

 hooks before, can it have four after, or vice versa ; and as the parts 

 are mostly composed of chitine, it is difficult to believe it can even 

 alter shape. 



