THE MARKINGS AND SHAPES OF BIRDS’ EGGS. 119 
shell is usually incomplete and uncolored, while that 
below is a bluish green. Many of the hawk forms 
appear (as they have grown more arboreal in their 
building) to have a tendency to lose those strong 
markings, and to dilute the deep stains which charac- 
terize the eggs of their ancestral relatives, the vul- 
tures. So also the flycatchers usually lay strongly 
marked eges, but the Phcebe’s are only specked occa- 
sionally, and the least flycatcher’s are always wholly 
white. 
Eggs frequently hint, though not always very re- 
liably, the kinship of the bird; and, strange to say, 
their very great variations may sometimes seem in- 
clined to point one way and sometimes the other. In 
fact, many of these variations must be the result of the 
double strain of kinship that comes into every family. 
Our crow blackbird lays two forms of eggs—one 
rather crowlike and one zigzagged, like those of the 
orioles. In its true kinship the bird stands where its 
egos indicate, between the oriole forms and the crow- 
jay forms. 
It would be interesting had we space to note the 
character of these markings and the relations they 
seem to sustain, to the ground colors; to the num- 
ber in the clutch; to the earliness or lateness of the 
clutch ; to the size of the egg, and even to the size of 
the bird; to the result of hybridism ; to the character 
of food; to the effect of fertilization; to the change 
of climate; and to the general bearing of the environ- 
ment. Few things are more fascinating than the study 
of birds’ eggs in this light. 
