The respiratory system in Arctocephalus australis (Pinnipedia, Otariidae). I--Macroanatomy and microanatomy of the trachea and extrapulmonary airways]

This paper presents the results of histological and histochemical organization of trachea and primary bronchi. The presence of a subepithelial lamina and a smooth muscle layer in the superficial corion, probably related with a functional respiratory mechanism are defined. The structure of tracheal and primary bronchi glands, the way they secretes and the type of secretion are also described.