of the Fishery Board for Scotland. 305 



Habitat. — On cod, pollack, and other fishes. This appears to be the 

 largest of the British Caligi ; the carapace of some of my specimens 

 measures 8 mm. in breadth. It is not so common as the next species. 



Caligus rapax, M. Edwards. 



1840. Caligus rapax, M. Edwards, ' Hist. Nat. Crust.,' iii. p. 453, 



No. 6, t. 38, fig. 9. 

 1850. Caligus rapax, Baird, ' Brit. Entom.,' p. 270, pi. xxxii. figs. 



2, 3. 



Habitat. — On various fishes, as the cod, saith, pollack, lumpsucker, 

 taken also with surface and bottom tow-nets. A common species. The 

 young (Chalimus scombri, Burmeister) frequent on the lumpsucker. 



Caligus mulleri, Leach. 



1816. Caligus mulleri, Leach, 'Enc. Brit. Supp.,' i. t. 20, fig. 68. 

 1850. Caligus mulleri, Baird, loc. cit, p. 271, pi. xxxii. figs. 4, 5. 



Habitat. — The abdomen of this species is decidedly shorter than that 

 of Caligus rapax, the shape of the carapace is also more oblong. It 

 does not appear to be very common. 



Lepeoptheirus pectoralis, Miiller. 



1776. Lernaia pectoralis, Miiller, 'Zool. Dan.,' i. p. 41, t. 33, 



fig. 7. 

 1832. Lepeoptheirus pectoralis, Nordmann, ' Mikr. Beitr.,' ii, p. 30. 

 1850. Lepeoptheirus pectoralis, Baird, loc. cit., p. 275, pi. xxxii. 



fig. 10. 



Habitat. — Adhering to the pectoral fins of the plaice ( Pleuronectes 

 platessa), frequent. Lepeoptheirus differs from Caligus by not having 

 sucking disks on the frontal plates. 



Lepeoptheirus thompsoni, Baird. 



1850. Lepeoptheirus thompsoni, Baird, loc. cit, p. 278, pi. xxxiii. 

 fig. 2. 



Habitat. — On the gills of the turbot ; frequent. In this species the 

 thorax is larger and the abdomen longer than in the previous one. 



Cecropid^:. 

 Cecrops latreillii, Leach. 



1816. Cecrops latreillii, Leach, 'Enc. Brit. Supp.,' vol. i. t. 20, 



figs. 1-5. 

 1850. Cecrops latreillii, Baird, loc. cit., p. 293, pi. xxxiv. figs. 1, 2. 



Habitat. — Attached to the gills of the short sunfish (Orthagoriscus 

 molce) caught in the Forth, October 1890 (Andrew Scott). This species 

 has been taken by Edward on the gills of both the short and oblong 

 sunfish in the Moray Firth. Specimens of C. latreillii, from the Forth 

 are also in the Edinburgh Museum (E. Clark). 



Lcemargus muricatus. Kroyer. 



1838. Lodmargus muricatus, Kroyer, ' Tidsskrift,' vol. i. p. 487, 



t. 5, figs. A, B, C, D. 

 1850. Lcemargus muricatus, Baird, loc cit., p. 295, pi. xxxiv. 



figs. 3, 4. 



Habitat. — Attached to cavities hollowed out of the flesh of a short 

 sunfish caught in the Forth, October 1890 (Andrew Scott). It has 

 also been recorded by Edward from the Moray Firth, from the same 

 species of sunfish. Laimargus appears to be more restricted in its habitat 

 than Cecrops. 



U 



