Penicil´late, a. Brushy-tipped.

Pe´nis, n. The male intromittent organ.

Pen´na, n. A feather. Generally a contour-feather (pluma), as distinguished from a down-feather (plumula); particularly, a large stiff feather of the wing or tail, one of the remiges or rectrices.

Penna´ceous, a. Denoting a perfect feather complete in all the parts a feather can have; distinguished from plumulaceous.

Pen´niform, a. Noting a muscle whose fibres are arranged alongside of a central tendon, like the web of a feather.

Per´forate, a. Pierced through. (Said especially of the nostrils when without a septum.)

Pericar´dium, n. Bag holding the heart.

Pericra´nium, n. Soft parts enclosing the skull; especially the periosteum of the bones.

Perios´teum, n. Membranous investment of bone.

Peripheral Parts, n. pl. Superficial, as opposed to interior, parts.