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Show 1901.] ON BUTTERFLIES FROM THE WHITE NILE. 25 4. On some Butterflies from the White Nile collected by Capt. H. N. Dunn of the Egyptian Army. By A R T H UR G. BUTLER, Ph.D., F.L.S., F.Z.S., &c. [Received November 14, 1900.] Although the number of species recorded in the present paper is small, several of them are of considerable interest. In the genus Teracolus are three interesting species-T. phlegyas, T. liagore, and T. glycera. The first Mas originally described from what I took to be the wet phase of the species, and which consequently was for some time confounded with the insect to which Miss E. M . Sharpe has given the name of T. diffic'dis; Capt. Dunn has now secured both sexes of the true wet phase, which shows that the nearest relation of T. phlegyas is T. bacchus (the form hitherto regarded as the wet phase being an intermediate phase of the species). T. liagore is represented in the collection by wet and intermediate phases ; the intermediate phase having both a large and small form, the large form will represent T. stygia of Felder, and the small form T. odysseus of Swinhoe. T. glycera, which I originally described from a single male example without definite locality, has now come to hand in all its seasonal phases, aud proves to be an easily distinguishable form of the T. aniigone group : the males always characterized by an unusually straight outer margin to the primaries and hardly a trace of the dividing spot at the posterior edge of the orange apical patch ; the female of the wet phase is dimorphic, either with an orange apical patch very distinctly divided by an angulated dusky line, or with the apex dusky brown enclosing four to five hastate yellowish streaks. Another species of interest, of which both sexes were obtained, is Belenois abyssinica of Lucas (the wet phase approaching typical B. c/idica), of which the Museum previously only possessed three examples ; this is the insect for which, thinking it undescribed, M . Oberthur has proposed to use M . Boisduval's M S . name of " Pieris allica.,, It is apparently strictly limited to N . Africa, though the (typical) dry-season phase more nearly resembles the dry phase of the widely distributed southern and eastern B. westwoodi than might be expected from a comparison of the respective wet phases of the two species. Perhaps one point of interest in this collection should be noted, namely, the resemblance of the species generally to, and their frequent identity with, those of Aden. At least fifteen of the Butterflies occurring at Aden are conspecific with those in the present collection, whilst Precis boopis and Teracolus liagore are nearly related to the Arabian forms; perhaps, however, the strangest thing is that Limnas chrysippus is tetramorphic both at Aden and on the White Nile, and it is probable that the same is true of Catopsiliaflorella, three of the four forms of that species being in the present collection. |