Larvae ofCeratophyllus wickhamiand other Species of Fleas

Abstract

A short historical account is given of the writings on flea larvae since the seventeenth century. The larvae have been known since Leeuwenhoek tried to breed them in 1683.The life-history ofCeratophyllus wickhamiis described. The fleas were bred in the laboratory on a grey squirrel. Three larval instars occur, and the life-history occupies, on an average, 6 weeks under experimental conditions.The external anatomy of the third instar larva ofC. wickhamiis described. The mouth parts are generalised and suggest the condition of a primitive insect. The tracheal system is composed of a double longitudinal trunk on each side, with spiracles on the prothorax, metathorax and first eight abdominal segments.The first and second instar ofC. wickhamiare similar to the third instar larvae, except in size and the presence of a hatching spine in the first stage.The larva ofCeratophyllus fasciatusis mentioned. The importance of the species lies in the presence of completely separated galea and lacinia.Larvae ofXenopsylla cheopisandX. astiaare briefly described. The larvae of the two species are practically identical except for the shape of the mandibles.