MAYER: COLOR AND COLOR-PATTERNS. 
261 
spots of different colors fuse, giving a chain of spots which are of 
one color above and another below. 
In F ig. 16 the spots composing the row BB are blue (dark) 
above, and red (light) below. It will be observed that the color is 
bilaterally symmetrical, as usual, about the axis through the middle 
of the cell. Such bicolored spots are often due to a simple fusion, 
as before stated; but sometimes they may, perhaps, be intrinsically 
bicolored. 
Fig. 15 is a beautiful instance of an exception to the general rule 
that spots are bilateral about the axis through the center of the cell. 
It is taken from Ornithoptera trojana Staudinger. 1 The light spots 
represented near the outer edge of the wing are of a brilliant irides¬ 
cent green. It is evident that they are distinctly bilateral with 
respect to the nervures ; especially is this true of the pair adjacent to 
nervure 1 . Ornithoptera brookiana Wallace illustrates another 
exception, though in a less marked degree. 2 Other allied species of 
Ornithoptera, however, w T ould seem to show that these apparent 
exceptions may have been derived from forms which exhibited two 
spots in each cell and followed the usual rule. These are the only 
instances of such exceptions known to me. I do not doubt, how¬ 
ever, that further study would reveal others. 
In Fig. 17 an example is given of the peculiar kind of eye-spots 
found in the Saturnidae. The species from which the figure was 
taken is Saturnia spini. It will be seen that this so-called eye-spot 
is quite different in formation from the ocelli of butterflies. It is 
simply a series of curved cross-bands between nervures, arranged 
symmetrically on both sides of the cross vein CC. The “ eye- 
spots” upon the wings of Attacus luna and in the genus Telea are 
also of this sort. True eye-spots, however, similar to those found 
among the Morphos and Satyridae, occur in moths, as in the apex 
of the fore wing of Samia cecropia, Callosamia promethea, etc. 
“ False ” eye-spots are also found on the wings of butterflies; in 
Vanessa io, for example, the so-called eye-spot of the fore wing has 
been shown by Dixey (’90) to be made up of a series of fused 
spots. It will be remembered that Merrifield (’94, Plate 9, Fig. 4) 
caused this “ ocellus ” to break up into its constituents by subjecting 
the pupa to a temperature of 1° C. The ocellus upon the hind wing 
of Vanessa io is no doubt a true eye-spot; the only evidence which 
1 See Watkins, ’91, Plate 4. 
2 See Hewitson, ’56-76, Vol. 1. 
