OF FISH OBTAINED AT PLYMOUTH. 157 



lupus, in June and October. The Hamulus acccssorius anterior is 

 particularly long, and the second maxillipedes in the male are very 

 strong and large. 



7. Caligus Millleri, Leach, was found on the surface of the body of 

 poor-cod, but was only seen on a few occasions, a large number of males 

 being taken proportionately to the females. The same Caligus was also 

 found on Trigla gurnardu^. 



8. Caligus curtus, Mi'dler. This species was taken frequently from 

 the mouth of the cod. Both the description and figure in Mliller's 

 work are very indefinite. This species differs from the latter in being 

 rather smaller, the furcula branches longer, and the abdomen rather 

 bigger. 



9. Caligus gurnardi, Kroycr. One specimen of this species was taken 

 from the gill cavity of Trigla cucuhis in June. 



10. Caligus hrevipedis, n. sp* Two specimens of this curious form 

 were taken, in August, from the gill cavity of Motella tricirrata. It 

 differs from all other described species in the rudimentary condition 

 of the fourth pair of thoracic limbs. The same character was found 

 in both specimens, so that it could not well be an abnormality. 



Lepeophtheirus, Nordmann. 



Frontal lobes without sucking discs ; fourth thoracic segment free ; 

 genital segment without lobes on the back ; abdomen appearing free 

 behind. 



a. Abdomen long, 



1. Lepeophtheirus stromii, Baird {vesper of Milne Edivards). Speci- 

 mens of both sexes of this species were found in quantity on the 

 surface of the body of salmon and salmon-trout in June and July. 



2. Lepeophtheirus pollachius, 7i. sp* Both sexes taken in quantity 

 from the palate and back of the tongue of Gadus pollachius, also from 

 the gills of the ling, Molva vulgaris. This species is nearly allied to 

 the last mentioned. 



3. Lepeophtheirus Thonipsoni, Baird. In the gills of turbot and brill, 

 Rhonibus maximus and laevis. The specimens of this species were 

 generally found in great numbers in the gills of the above-mentioned 

 fish ; I have taken as many as thirty from one. The specimens 

 described by Kroyer as L. rhombus is closely allied in detail, but the 

 carapace as represented by him is very small and round, whereas in 

 this species it is large and distinctly oval, as shown by Baird. 



4. Lepeophtheirus ohscurus {?), Baird. Found in the gills of Rhombus 

 laevis only. This species has outwardly a very close resemblance to 



* See former note, p. 156. 



