REVISED REPORT ON L.M.B.C, COPEPODA. 913 
from those figured by Claus chiefly in the form of the 
prehensile posterior antenne and in the segmentation of 
the abdomen; but this animal appears to vary much in 
these very particulars according to age and sex, and it is 
therefore quite likely that Claus’s specimens may repre- 
sent slightly different stages of development. The group is 
extremely interesting, as exhibiting progressive and retro- 
gressive development, and deserves more attention than it 
appears to have hitherto received. The female is about 
1-18th inch in length, the male rather smaller, and the 
larval form about half the size of the female. 
Since the above were recorded Prof. Herdman has found 
a number of adult specimens of Lernea branchialis ad- 
herent to the gills of whitings taken in the Rock Channel. 
Family LERN#OPODID2. 
Anchorella uncinata, Miller. (Pl. XX VII, fig. 2.) 
Length (without ovaries) 2.20 mm. Several specimens 
were found by Mr. Corbin on the gills of whiting taken in 
the Mersey estuary. Microscopical examination of one 
of them in situ shows the parasite impaled by the rounded 
knob at end of arms to one of the clusters of gill rakers 
which occurs at regular intervals along the concave side of 
the branchial arches. These rakers serve to arrest the 
passage of any solid substances into the gill cavities and 
appear also to form a secure anchorage for parasites which 
in Anchorella are surrounded by a tough transparent 
membrane. There are no males among those I have 
examined. 
EXPLANATION OF PLATES. 
PLraTe XV. 
Fig. 1. Calanus finmarchicus, Gunner. a, Rostrum, 
b, terminal spine of swimming feet. 
