466 Mr. G. A. K. Marshall on 80. Description and Discussion of Material bearing ON Mimicry in South African Rhopalocera col-lected BY Guy a. K. Marshall, and the Record OF Observations isiade ]5y him. (E. B. P.) Tlie splendid material which is described and discussed below has gradually accumulated as the result of Mr. Marshall's kind and generous response to my desire for specimens for the Hope Department illustrating the fact that mimetic species and their models, and the members of large convergent or synaposematic groups, not only in-habit the same areas but Hy together at the same time. The study of this material naturally led to conclusions and suggestions which it is hoped possess a general interest in relation to the doctrine of evolution and the important part which mimicry plays in it, as one of the chief evidences of the operation of natural selection. These more general discussions are placed under separate headings immediately after the groups whose study gave rise to them. The last sub-section is placed under Mr. Marshall's name, being quoted in cxtenso from his letters. A. Bladc-imd-Whitc Amauris-lilcc GrouiJ. The central model for the group described below is probably Amauris ochlca, but it was not captured on March 27, 1897, when five convergent individuals were taken at Malvern, near Durban, Natal. The group as captured is as follows : — Planema aganice $. „ esebria $, var. witli white markings. Neptis agatlia $. 2 Kydcviera leuconoe. The male Planema aganice is but an imperfect member of the group, the lighter markings being buff instead of white, as in the female. We thus find that the latter sex forms closer synaposematic resemblances than the male, when the two sexes difiler. It is probable that this rela-tionship between male and female will be found to be generally true of MUllerian mimics in which the sexes exhibit diftereut degrees of hkeness to the type of some group characterized by Common Warning Colours. Fur-thermore, the culmination is often reached in Mlillerian
30. Description and Discussion of Material bearing on Mimicry in South African Rhopalocera collected by Guy A. K. Marshall, and the Record of Observations made by him. (E. B. P.)
BioStor
