JAMES NEWTON BASKETT. 97 
of egg-formation. But, so far as known, no reptile exhibits 
anything like it, so that color in birds’ eggs is likely signi- 
ficant, and this form of nesting may be a degeneration. 
The greens and blues noted accord well with living 
vegetation. Perhaps their persistence now as the basis of 
modern ground-colors is due to the persistence of chlorophyl. 
The leaf is older than the egg. At least they seem now to 
be the only colors inherently or deeply involved within the 
shell, and they show evidences of being the basis of the 
deepest or earliest spotting. Perhaps the first divergence 
from sand-nesting and the first step toward incubation was 
by placing the eggs upon growing vegetation ; and the browns 
may have come in later, as indicated in their usually being 
more superficial (whether as spots or continuous coloring), 
and typify a time when dead grass became the nest- 
material. This was an era of progress, perhaps, for dead 
grass means after separation from its root, and thus hints at 
nest-building on the part of the parent. 
The browns are perhaps founded in the solid suffusions 
of the creams and buffs so frequently yet seen in our 
grounds; and are doubtless held there yet by the persistence 
of the old superinducing influence of the strawy color of 
ripened vegetation so much used in nest-structure. 
That the blues are very basic is found in another fact, 
that in some eggs they pervade the shell to the interior in 
great intensity. In a broken egg of the Turkey Vulture 
(Cathartes aura) in my collection, many spots that are faint 
lilac externally show on the inside as a deep indigo blue, 
while the pale browns are not visible at all from beneath 
except by transmitted light. In the egg of a Bartram’s 
Sandpiper (Bartramia longicauda) there are faint brown 
spots on the outside which have no internal showing, and 
faint bluish spots inside that do not show at all outwardly, 
even in the unmarked places. To my mind the suggestion 
comes that many of our early birds with spotted eggs may 
have reverted from green and dead grass nesting to shingly or 
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