Observe the strongly basophilic hyaline cartilage (H) in this slide (40X) of the trachea. It is a part of a cartilaginous ring of the trachea from a young kitten. Identify the lighter, acidophilic perichondrium (P) which invests the cartilage. The outer, convex, layer of perichondrium seems to be relatively thicker and more active. Why? Also, recognize that the trachealis muscle (left edge of - M) (smooth muscle) is attached at one point to the perichondrium - don't mistake it for perichondrium. Part of the esophagus is also visible at the right of field.