. Evolution and its relation to religious thought . ^. Fig. 35.—External anatomy of Caloptenus spretus, the head and thoraxdisjointed ; up, uiopatagium ; /, furcula; c, cercus (drawn by J. ). HOMOLOGIES OF THE ARTICULATE SKELETON. 125 regions, viz., cephalo-thoras and abdomen. In insectsthey arc grouped into three yery distinct regions—head,thorax, and abdomen. In insects, therefore, we find forthe first time the head distinctly separated from the restof the body. This is an evidence of high grade, becauseit shows the dominance of head-functions. The insect, such, for example, a
. Evolution and its relation to religious thought . ^. Fig. 35.—External anatomy of Caloptenus spretus, the head and thoraxdisjointed ; up, uiopatagium ; /, furcula; c, cercus (drawn by J. ). HOMOLOGIES OF THE ARTICULATE SKELETON. 125 regions, viz., cephalo-thoras and abdomen. In insectsthey arc grouped into three yery distinct regions—head,thorax, and abdomen. In insects, therefore, we find forthe first time the head distinctly separated from the restof the body. This is an evidence of high grade, becauseit shows the dominance of head-functions. The insect, such, for example, as a grasshopper, con-sists of seventeen or eighteen segments (Fig. 35). Ofthese, four belong to the head, three to the thorax, andabout ten to the abdomen. Those of the abdomen areall separated and movable ; those of the thorax and headare more or less consolidated. The appendages of thehead-segments become antennse and jaw-parts, 1. e., mandi-bles—maxilla and labium ; the appendages of the thorac-segments become legs (the wings are not homologouswi
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Keywords: ., bookauthorlecontej, bookcentury1800, bookdecade1880, bookyear1888
