. Evolution and its relation to religious thought . •^cc^ Fig. 10. Fig. 11. Fig. 12. Fig. 13. Figs. 10-13.—10. Fore-limb of bat. 11. Bird. 12. Archseopteryx. (Lettered as in previous figures ; grouped from varioussources.) it is a separate bone as large as the blade-bone itself,jointed with the latter at the shoulder and with thebreast-bone (sternum) in front, thus making together astrong shoulder-girdle for the attachment of the fore-limb. This was undoubtedly the condition in the origi-nal or earliest walking animal, viz., reptiles. It wasinherited and retained by birds, beca
. Evolution and its relation to religious thought . •^cc^ Fig. 10. Fig. 11. Fig. 12. Fig. 13. Figs. 10-13.—10. Fore-limb of bat. 11. Bird. 12. Archseopteryx. (Lettered as in previous figures ; grouped from varioussources.) it is a separate bone as large as the blade-bone itself,jointed with the latter at the shoulder and with thebreast-bone (sternum) in front, thus making together astrong shoulder-girdle for the attachment of the fore-limb. This was undoubtedly the condition in the origi-nal or earliest walking animal, viz., reptiles. It wasinherited and retained by birds, because necessary forpowerful action of the wings in flight. In mammals itgradually dwindled and became united with the blade-bone as a process. In one mammal, the lowest and most 98 EVIDENCES OF THE TRUTH OF EVOLUTIOK reptilian living—the ornithorliynclius—tlie coracoid ismuch like that of re|)tiles—a large, flat bone, separatedfrom the blade-bone and articulated with the breast-. FiG. 14. Fig. 15. Fiu. 16. Fig. 17. Figs. 14-17.—14. Fore-limb of turtle. 15. Mole. 16. Whale. 17. Fish. bone. It is a significant fact that, in the mammalianembryo, it is first developed as a separate bone andafterward united with the scapula. 3. In man, monkeys, bears, and some other mam-mals, the limb is fairly free from the body and the el-bow half-way down the limb ; while in herbivores (, 9), such as the horse, ox, and deer, etc., the elbow ishigh on the side of the body, and the limb is free onlyfrom the elbow downward. Perhaps in these cases mostobservers do not recognize it as an elbow at all. Allgradations between these extremes are easily free condition of the limb is evidently the originalone, the condition in herbivores being an extreme modi- PEOOFS FROM HOMOLOGIES. 99 fication associated with another modification mentionedunder 5. 4. In man and in many mammals, and in all reptilesand birds, there are two bones in the forearm (radiusand ulna). In the mo
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