This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.
The diaphragm is the chief characteristic of mammalian myology. The amphibia and animals below them in scale of structure have no diaphragm. The first distinct trace of it may be found in crocodile and bird, where the muscular fibers which are concerned in its formation arise from ribs. Even animals as high in the ascending scale as birds have an imperfect diaphragm; it does not separate the lungs and abdomen of aves completely. In fact several descriptions have appeared as to what is considered a diaphragm in birds. A complete diaphragm which arises from the vertebral column, ribs and sternum is a mammalian property only. The exact mode of the formation of the muscle is not fully known. The mammalian diaphragm is probably homologous to the so-called diaphragm of other vertebrates. The mammalian diaphragm is supplied by the phrenic nerves, which arise from the fourth, fifth and sixth cervical nerves
ROBINSON B. THE DIAPHRAGM AND CENTRUM TENDINEUM. WITH TEN ORIGINAL ILLUSTRATIONS BY THE AUTHOR. JAMA. 1897;XXVIII(5):203–207. doi:10.1001/jama.1897.02440050011001b
Customize your JAMA Network experience by selecting one or more topics from the list below.
Create a personal account or sign in to: