1897.] Nocturnal Protective Coloration of Mammals, Ete. 101 
conspicuous in the daytime. I have noticed that when these 
large butterflies are roosting at night on goldenrods and other 
favorite flowers, with their wings folded up over the back, 
their colors not only blend with those of the flowers but their 
silvery spots shine in the moonlight like the dewdrops that 
surround them. 
Many birds, insects, etc., have acquired colors that are equally 
protective both by day and by night. This is true inthe case 
of the green colors of those that live on or amongst foliage, and 
in the case of those that have dull gray and brown colors, imita- 
tive of the bark of trees on which they rest. It also applies 
to bright colored insects that live on flowers of the same colors. 
But the multitudes of cases, which cannot be explained in 
this way, are probably due to special nocturnal protection. 
Many fishes that rest at night amongst the stems of aquatic 
” grasses, sea-weeds, etc., have dark or black stripes crossing the 
body transversely, obliquely, or longitudinally. Such colors 
are highly protective at night, when they are most exposed to 
their predaceous enemies, for the dark bands then resemble the 
dark stems and shadows of the weeds, and serve admirably to 
conceal the outline of the fish. Black fins and tails serve a 
similar purpose. Such markings of fishes are generally more 
distinctly developed at night than in the day time, as explained 
in the next article. 
In a similar way, the striped colors of the tiger are doubt- 
less more effective for concealment at night, or in the dusk of 
evening, among the stalks of reeds and shrubs, than in the 
day time. The same is true of the colors of the spotted jaguar, 
leopard, etc. 
The common raccoon is fairly well protected even in the day 
time by its gray fur, when resting on the large gray branches 
of trees, but as it generally hides by day in holes, we must 
regard its peculiar coloration as due to nocturnal protection, 
for which it is emniently adapted. 
