pl. XXI, fig. 1-4 and 10-40). The four Insects occur together at the 
same time of the year in Uganda. We have only lately become aware 
of the existence of this association, the male of Planema macarista 
being generally confounded with that of Planema poggei nelsoni 
and the female of macarista with some other Planema. All four 
males and the two females ne/soni (fig. 4) and hypoxantha (fig. 40) 
have a broad orange band on the forewing and a white band on 
the hindwing. The other two females, macarista 9 (fig. 2) and 
hobleyi Q (fig. 2a), differ from them remarkably in having a 
white band on the forewing. Our reasoning mind can hardly 
be satisfied by attributing the coexistence of these four Insects 
in the same limited locality to coincidence. We require some 
better explanation. Evolutionists account for such resemblances 
in different ways, which are more or less antagonistic. Firstly, 
it is said that inherent or constitutional forces of development 
modify a species in a certain definite direction. These directions of 
development in the various species of a family or order are few in 
number. The species of the same group or family or order being 
descendants of a common ancestor, it must necessarily happen that 
the line of development followed by a certain organ, f. i. the wing- 
pattern, is the same in a number of species (Parallel development), 
or that this organ has become but very little modified. Examples : 
Neuration has on the whole remained of great uniformity among 
the Lepidoptera and exercises a decided influence on the wing- 
pattern. Some authorities consider the wing-pattern of certain 
mimetic females, for instance in Papilio and /Hypolimnas, as a 
relic. Several Indian Papilios have preserved tails, whereas their 
representatives from the Moluccas or New Guinea have lost them. 
The same phenomenon is met with in some Papilios from South- 
Eastern Brazil as compared with the forms from the Amazons. 
Many African Butterflies have preserved a more ancestral pattern 
in East Africa than at the West Coast. On the island of Celebes 
the majority of Papilios as well as many other Butterflies have 
acquired a long forewing with a strongly arched costal margin. 
Among island Coleoptera derived from winged forms there are many 
which have lost the power of flight. The loss of power of flight 1s 
frequently accompanied in Moths by shagginess of the body. 
Secondly, it is further maintained that development by consti- 
tutional forces may also lead to similarity in two originally differ- 
ent species, if the lines of development are convergent. The lines 
