218 
A Parasitic Copepod 
These tubes are paired, for although only one is preserved entire in each of 
the specimens, the broken end of the second is present in the best specimen 
(Fig. 6). The tubes are attached to the vulvae of the female and communicate 
directly with the spermathecae, the ovisacs issuing forth dorsally at another 
aperture. The reproductive system is on the same general plan as I have 
described for Lernaeopoda ( Parasitology , vm. 269 and Fig. 6), the ovaries 
occupying the arcuate lateral portions of the genital segment. 
Fig. 6. Medesicaste. A diagrammatic representation of the relative positions of the two sexes 
with regard to the tumour on the host. T. tumour; G.F. gill filaments of host; $ female 
animal; <$ male animal; C.T. conjunctive tubes. 
A most remarkable phenomenon is that the other end of the tube, which 
is long, free, flexible and sinuous, enters the upper portion of the same tumour 
as that in which the head and neck of the female are embedded, where it 
bifurcates; hence the term “conjunctive” (Fig. 6). The tube is one third the 
width of a gill filament, and about 12 mm. long. 
The tumour produced by the parasite is structureless and is to be regarded 
as a hypertrophied gill filament. It may be irregular, but is usually clavate, 
