. The descent of man, and selection in relation to sex. Evolution; Heredity; Human beings; Natural selection. aspera l^ars on the extremity of his snout an appendage half as long as the head. It is cylindrical, covered with scales, flexi- ble, and apparently capable of erection : in the female it is quite rudimental. In a second species of the same genus a terminal scale forms a minute horn on the summit of the flex- ible appendage; and in a third species (C Stoddartii, fig. 34) the whole appendage is converted into a horn, which is usually of a white color, but assumes a purplish tint when th
. The descent of man, and selection in relation to sex. Evolution; Heredity; Human beings; Natural selection. aspera l^ars on the extremity of his snout an appendage half as long as the head. It is cylindrical, covered with scales, flexi- ble, and apparently capable of erection : in the female it is quite rudimental. In a second species of the same genus a terminal scale forms a minute horn on the summit of the flex- ible appendage; and in a third species (C Stoddartii, fig. 34) the whole appendage is converted into a horn, which is usually of a white color, but assumes a purplish tint when the animal 28 excited. In the adult male of this latter species the horn is half an inch in length, but it is of quite minute size in the female and in the young. These appendages, as Dr. Glin- ther has remarked to me, may be compared with the combs of gallinaceous birds, and apparently serve as ornaments. In the genus Cha- mseleon we come to the acme of difference between the sexes. The upper part of the skull of the male (C bifurciis (fig. 35), an inhabitant of Mada- gascar, is produced into two great, solid, bony projections, covered with scales like the rest of the head; and of this wonderful modifica- tion of structure the female exhibits only a rudiment. Again, in Chai7iceleon Owenii (fig. 36), from the West Coast of Africa, the male bears on his snout and forehead three curious horns, of which the female has not a trace. These horns consist of an excrescence of bone covered with a smooth sheath, forming part of the general integuments of the body, so that they are identical in structure with those of a bull, goat, or other sheath- horned ruminant. Although the three horns differ so much in appearance from the two great prolongations of the skull in C. bifurcus, we can hardly doubt that they serve the same general purpose in the economy of these two animals. The first conjecture, which will occur to everyone, is that they are used by the males for fighting together; and, as
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Keywords: ., bookcentury1800, bookdecade1870, booksubjecthumanbeings, bookyear
