1902-1903.] Distribution of the Smaller Crustacea. 33 



A copepod is found on the hake {Merlucius merluccius) which 

 differs from many others in the mode of its attachment. This 

 species, instead of fixing itself to some vital part of the fish, 

 such as the gills, sends out a process which penetrates one of 

 the scales, and expands between the outer and inner surfaces 

 of the scale into a thin round disc, which is ornamented with 

 several clear narrow slits arranged like the radii of a circle : 

 it is from this latter peculiarity that the species derives its 

 name of Anchorella stellata. It is scarcely possible to remove 

 the copepod without also removing the scale along with it. 

 All the specimens I have hitherto noticed have been attached 

 to scales in the neighbourhood of the pectoral and ventral fins, 

 especially the former. The first specimens observed looked 

 like globules of semi-transparent mucus, but finding that the 

 globules were somehow fixed, I was led to examine them more 

 closely, and so was enabled to add another species to the 

 copepod fauna of our seas. I have so far only found this 

 parasite on hake sent from the Clyde, but it is likely to occur 

 on the same fish from other parts of our coast. It is interest- 

 ing to note that Kroyer, who first described the species, 

 obtained his specimens also from the hake. 



Another parasitic crustacean, remarkable because of its size 

 and from the position in which it is found, is the large Charo- 

 pinus dalmanni of Eetzius. This species is usually found in 

 the spiracles of the grey skate {Raia hatis), and adult female 

 specimens attain a length of fully two inches. I have some- 

 times found the parasite in both the spiracles of the same 

 skate, and frequently two, and occasionally three, specimens in 

 the one spiracle. The species is not uncommon on large grey 

 skate brought to the Aberdeen fish-market, and it has also 

 been obtained on a grey skate captured at the mouth of the 

 Forth estuary. Two other species of Charopinus have been 

 recorded — viz., C. ramosus, Kroyer, found on Eaia clavata and 

 Haia maculata, and C. dubius, found on Raia circularis ; but 

 these two species are usually found on the gills of the different 

 skates, instead of in the spiracles. 



Two parasitic copepods belonging not only to two different 

 genera but also to two different families have been found on 

 the gills of the spotted dragonet {Callionymus maculatus). 

 The one is called Hcemohaphes amhiguus, and belongs to the 



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