88 LÉPIDOPTÉROLOGIE COMPARÉE 



are, it is true, localities in each division where one form, so to 

 speak, appears as an occasional aberration of another form; the 

 dividing line, also, cannot be drawn with distinctness in certain 

 areas, and transitional forms necessarily occur. Also there are 

 undoiibtedly one or two places where two forms appear together, 

 " areas of intermixture ", as Dr. Buckell calls them. But, on the 

 whole, it vvill be found that the arrangement by forms is well 

 warranted, and that the areas of intermixture are so few and far 

 between as to constitute almost a quantité négligeable. 



Original descriptions, and discovery in Britain. 



Before proceeding to cite the history and trace the distribution 

 of tiphon and its forms in Britain and Ireland, it may be as well 

 to recall the original descriptions of the several forms enumerated. 

 Von Rottemburg's original description of the species (Natnr- 

 f or s cher, VI, p. 15) was made from examples captured near Halle 

 in Germany, and I gladly avail myself of the late Mr. W. F. Kirby's 

 translation {A Handbook to the Order Lepidoptera, i8g6, Part. I. 

 Butterflies, Vol. I, p. 221). 



" Very like C. pamphilns, but larger; sometimes nearly twice 

 as large. Wings nearly uni form in colour above and below. Fore 

 wings almost always showing one or two indistinct eyes; hind 

 wings with at most one or two indistinct eyes near the anal angle. 

 Eyes distinct beneath; fore wings with one eye at the tip, and 

 rarely one or two smaller ones. Hind wings grey, with a white 

 transverse band, which is much interrupted, and sometimes reduced 

 to two white spots. Hind wings with five or six eyes parallel to 

 the hind margin, the uppermost largest; that nearest the anal 

 angle often double, or represented by two very small eyes close 

 together. The insect varies greatly in the size and number of the 

 eyes. " A reasonably close description of our typical tiphon though 

 it is a pity that von Rottemburg's ill spelling is perpetuated by 

 the law of priority sensu stricto. 



