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Show Birds' Eggs of Varied SizU "The smallest bird's cgs is that of the humming bird, the largest is that of the extinct nepyornK which held six times as much as the ostrich's and a hundred and fifty times us much as a fowl's," says Prof. J. Arthur Thomson In his "Biology of Birds." "It is said that the et-g of the extinct nioa sometimes some-times measured 9 inches in breadth and 12 in length, but that of the aepyornls was far larger. Of European Euro-pean birds, the swan has the largest egg, the goldcrest the smallest. What Is the biological significance of the difference In size? "When a bird lays only one egg It Is likely to be relatively large, ns In guillemot, gannet and puffin, it may be noted that these birds lay In places where enemies are few and where It Is not dangerouB that the eg should have a conspicuous size. The e'gs of the wingless kiwi of New Zealand are larger In proportion to' the bird's size than In any other case, and It Is Interesting Inter-esting to notice that they (usually two) are stowed away in a nestat the end of a tunnel In the ground." |