Pteroessa, [224]

Pteronella, [73]

Pterostichus niger, infested by Gordius, [170], [170], [172]

Pterosyllis, ciliated lappets, [273] n.

Pyriform organ, [509], [511]

Quatrefages, on Gephyrea, [411], [445]

Rabbit, parasites of, [141], [145]

Ragworm, [322]

Railliet, on Cestodes, [91]

Rami, in Rotifers, [210]