1882.] 109 



RE-DISCOYERY OF PJERLA FEREERI, PICTET. 



BY R. McLACHLAN, F.R.S., &c. 



So far as I am aware, nothing has been published concerning 

 Perl a Ferreri since it was first described by Pictet in his " Perlides,^' 

 p. 210, pi. xviii, figs. 1 and 2, more than 40 years ago (1841). He 

 wrote. — "La Perla Ferreri se trouve dans les environs de Turin ; le 

 Musee de Geneve en possede deux exemplaires males qui faisaient 

 partie de la collection qui lui a ete leguee par M. le Chanoine 

 Ferrero." 



The species is remarkable from its ample (even in the ^ ) blackish 

 wings, nearly wholly black head and thorax, and yellow abdomen, 

 with black tails. 



At Geneva, I had the opportunity of seeing the two typical males, 

 which, at present, are not in the Museum, but at the residence of the 

 widow of the late A. Edouard Pictet (son of the describer). But I 

 was not able to make a critical examination. 



When in the beautiful Val Anzasca, on the 17th July, I visited 

 the pretty waterfall that descends from below the mountain village of 

 Calasca, and at its foot captured a female Perla that is undoubtedly 

 Ferreri. It quite agrees with Pictet's description, excepting sexual 

 differences. 



The anterior-wings expand to 51 mm. (Pictet gives 41 mm. for 

 the (^). As structural sexual characters, it should be noticed that the 

 margin of the last dorsal segment is truncate, and that the egg-valve 

 is rather large and semicircular. It was not remarked in Pictet's 

 desci'iption that the anterior margin of the wings (costal and sub- 

 costal areas) are slightly tinged with greenish in the living insect, but 

 this tinting is a character common to many PerlidcB ; in this case it 

 chiefly results from the costal and sub-costal nervures, and the costal 

 nervules, being of a paler colour than the rest of the neuration (which 

 is blackish). 



Entomology awaits the advent of some one with sufilcient courage 

 to attack the Perlidce (even the European species) in a monographic 

 manner. Pictet's work was admirable, as all those who have had 

 occasion to consult it will readily admit; but it requires supplementing 

 in accordance with the experience gained during the more than forty 

 years that have elapsed since its appearance. When I regard my own 

 accumulations of materials in this family (even in European forms), 

 and feel to what a small extent they are arranged and determined, the 

 question constantly recurs to me : — Will a specialist in Perlidce ever 

 appear ? 



Lewisham : August, 1882. 



