74 



THE ENTOMOLOGIST. 



be hardly convenient for reference, especially when it possibly 

 happens that even the name of the species, about which we want 

 to learn something, is unknown to us. The student of the 

 larger groups of British Lepidoptera is assisted in his investiga- 

 tions by works treating of the particular group or groups he may 

 wish to study, but should he be inclined to turn his attention to 

 our species of Pterophori he is left very much to his own 



resources. It may be suggested 

 Fig. 1, that we have some account of 



the group in Mr. Stainton's 

 ' Manual.' True ; in that ex- 

 cellent epitome of British Lepi- 

 doptera, short descriptions are 

 given of the imagos of some 

 thirty species of "plumes," but 

 no mention is made of their 

 larvae, except as regards the 

 food-plant. The ' Manual' was 

 published in 1859, and since 

 that time, with the exception 

 of the life-bistories just re- 

 ferred to, no attempt has been 

 made to give a systematic his- 

 tory of the British Pterophori. 

 In describing, I shall not 

 aim at the production of an 

 elaborate scientific descrip- 

 tion ; but I hope, by directing 

 attention to the more im- 

 portant specific variations of 

 formation and markings, to 

 enable the student to deter- 

 mine his captures in this 

 group with precision. 

 The initial step, in identifying a species of the PteroplioridcB in 

 the imago state, is to note the structure of the anterior wings. 

 These are — with the exception of Agdistes Bennettii — always 

 more or less cleft on the hind margin, sometimes so deeply as to 

 separate the wing into two distinct digits ; in other cases only 

 dividing the wing into two lobes. I propose to use the term . 



Tig. 2. 



Fig. 1. — P. lithodactylus. a, digital 

 juncture ; b. outer digit ; c. tip of outer 

 digit; d. tip of inner digit; e, angle of 

 outer digit ; /, inner digit ; c/. angle of inner 

 digit; h. l>st feather of hind wing; /. '2nd 

 ditto ; j. ;3rd ditto. 



Fig. 2. 

 wing. 



-P. trirjonodactylus. — Anterior 



