GENERAL LAWS OF ANIMAL STRUCTURE. 



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may be regarded as the original form of the land animal. 

 In these all the parts are large. The coracoid is as large 

 as the blade, and is joined firmly to the sternum, making 



thus a firm girdle for the attachment of the fore limb. 

 In birds also the coracoid is a large bone firmly united 

 to the breastbone (sternum). These are types of shoul- 

 der girdle. In man the coracoid is reduced to a small 



