452 
But in my opinion in order to judge about the interrelations of 
the colour-patterns of Saturnia, it is absolutely necessary to compare 
with each other as many different forms as possible, just as in the 
case of other groups of Lepidoptera. It certainly cannot stand eriti- 
cism to draw consequences from the exclusive consideration of three 
intimately connected species as to the relative age of their colour- 
patterns. 
When pursuing this broader way, the well-foundedness of the 
above-mentioned assertion, viz. that the colour-pattern of Saturnids 
is a special case of that of Bombycids, and the latter again of that 
of Heterocera in general, is clearly proved. To begin with: next to the 
three above mentioned species stands Saturnia (Caligula Jordan) 
boisduvalif, on whose upper side the submarginal dark seam 
broadens from before backwards in still higher degree than in pyri, 
which reduces the somewhat median clearer area under the eye- 
spot, (broadest in pavonia) to almost nothing by forcing it back 
in proximal direction. 
The two dark borders by which this area is limited (and which 
I suppose to be V and VI) are in one place locally connected by 
a black transversal link. This part of the pattern of boisduvalii 
therefore shows the greatest similarity with the corresponding area 
of the pattern of the male pavonia, but in the latter the connecting 
link seems to run between IV and V. Generally speaking, it is not 
easy accurately to make out the exact consecutive number of the 
bands for each separate form, yet the comparison of the superior 
surface of the different species leaves the general impression, that 
the posterior broadening of the dark submarginal area is brought 
about by the progressive darkening of the colour in a proximal 
direction, which consecutively incorporates the dominion of a more 
proximally situated transversal bar. In the female of pavonia this 
darkening process is restricted to the area of Bar II, in the male it 
has advanced unto III, in the same way as in both sexes of spini, 
in pyri it has reached IV, in boisduvalii V. 
On the inferior surface the broadening of the dark area proceeds 
more slowly and more equally over the whole extension of the dark 
submarginal field. Consequently the underside of spini e.g. resem- 
bles both the upper- and the underside of pavonia to a higher 
degree than its own superior surface. On the hindwing the back- 
ward broadening of the dark submarginal border is less pronounced 
than on the forewing, and this edge is there separated by a light- 
coloured band over its whole length, from the dark festooned line, 
that runs along the distal side of the eye-spot. 
