858 MR. G. MAW ON THE LIFE-HISTORY OF A CROCUS. 
pronounced featherings are external, there are a few species (e. g. 
C. zonatus, C. pulchellus, and C. vallicola) in which the purple 
veining is on the inner surface. 
In the blue and white species the featherings are purple, and 
in the orange species rich brown; but in each case the colour- 
cells of the external featherings are purple, the brown colour of 
the featherings of the orange species being due to the overlay of 
purple on the orange ground. 
In the pale forms and albinos of the orange species, the fea- 
therings appear as purple instead of brown. 
The presence of feathered markings is not a stable specific 
character, as the majority of the species vary with self-coloured 
flowers and with flowers externally striped and feathered. 
Indeed, colour is of the least importance for specifie distinction. 
Nearly all the Cyanie species vary in every shade of colour and 
with white flowers; and even the Xanthie species occasionally 
vary to white, and even blue, but this is very exceptional: and 
the Xanthie species are more constant in their colouring than 
the Cyanie. I know of no case in which a Cyanie species varies 
with orange flowers, though Herbert was bold enough to place 
the orange C. susianus as a variety of the lilac C. reticulatus, and 
C. chrysanthus and C. biflorus as varieties of one species; but 
this view cannot now be accepted. 
There are two or three special points in colour-variation which 
must be noticed. A few species (e. g. C. vernus, C. asturicus, C. ver- 
sicolor,and C. acrius) are essentially various in their colouring; and 
intheseit is difficult to find two flowers precisely similar evenin the 
same habitat. There are other species that are perfectly constant ; 
and again those that are similarly coloured in the same habitat, 
but which present geographical variations—e. g. C. cancellatus at 
its western limit, in the Ionian Islands, has white flowers; east- 
ward, in Greece, the segments put on a lilac tint; still further 
to the east, in Asia Minor, the colour deepens ; and in Syria and 
Cilicia C. cancellatus occurs only of a clear purple colour. This 
tendency to change, eastward, from white to purple does not 
stand alone, and is also noticeable in C. biflorus. The Italian 
form is generally white, varying occasionally with lilac; but in 
Georgia, in the variety of biflorus known as C. Adami, the limb 
1s invariably lilae or purple. 
There are also many cases of mimetic variation—two distinct 
species putting on, in the same district, some identical form of 
marking or colouring. I shall have further to refer to this in 
