A Parasitic Copepod belonging to the Genus Medesicaste (Krøyer), and its Relation to the Tumours it produces on the Fish, Trigla gurnardus

Abstract

A tumour among the gill filaments of Trigla gurnardus bears a female Medesicaste with the head and neck buried in its apex, and a male Medesicaste completely embedded in its base. The two sexes of the parasite are connected by a conjugation tube, external to the tumour, down which tube the spermatophores presumably pass. The appendages of the copepod are described.