The Mammalian presternum (manubrium sterni) and xiphosternum have the same origin as the main body of the sternum (Ruge, No. 438).
Episternum, ep-i-ster′num, n. the interclavicle: the epiplastron: the presternum of mammals.
In the Chiroptera the presternum is strongly keeled and so is sometimes the mesosternum.
The presternum has a prominent keel for the attachment of the pectoral muscles.
In the ant-eaters and armadillos the presternum is broad and sometimes as in Priodon strongly keeled.
The two clavicles are joined across the top of the presternum by an interclavicular ligament.
The presternum is as a rule small and compressed, often much keeled, especially in the horse and tapir.
In all bats the presternum has a prominent keel for the attachment of the great pectoral muscles.
presternum pre·ster·num (prē-stûr'nəm)