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 CRUSTACEANS ' A number of specimens have since been found in material washed from Ophiuroids {Ophioglypha and Ophiothrix) taken in the trawl-net off Blackpool, and sent to us by Mr. Ascroft.' He further remarks that ' This species is readily distinguished from the other members of the Ascomyzontidae by the almost oval outline of the cephalothorax, and on dissection, by the structure of the mandible palp and maxillas ; the stout seta on the larger lobe of the maxillas appears to be a well marked character.' For the fish parasites among the Copepoda of this county the arrange- ment adopted by Mr. P. W. Bassett-Smith, R.N., F.Z.S., may suitably be followed.^ In the family Ergasilidas stands Bomolochus solea (Claus), reported by Mr. A. Scott, ' From small cod caught in Barrow Channel,' with the remarks that ' A number of specimens of this copepod can usually be found by pressing the nostrils of cod, so that mucus, etc., may be ejected : the mucus is then placed in a drop of water, and the copepods, if present, are easily seen : the females have two large white tgg sacs.' ^ The family Caligidas comprises Caligus minimus (Otto), ' frequent in the mouth of the Bass {Labrax lupus), caught in Barrow Channel, August, 1900'; C. brevicaudatus (A. Scott), ' inside the mouth of the Common Gurnard [Trigla gurnardus), caught in the vricinity of Piel, August, 1901,' and distinguished in the genus by 'the ex- tremely short abdomen and caudal stylets,' as also by ' the fourth pair of feet, the exopodite of which is very slender' ; Pseudocaligus brevipedis (Bassett-Smith), of which a number of specimens ' were found inside the operculum of a three-bearded Rockling [Onus tricirratus) caught in Barrow Channel,' the new genus being characterized by Mr. Andrew Scott as having ' Fourth pair of feet very rudimentary, almost obsolete, consisting of a basal portion only ; no exopodite as in Caligus^ ; Lepeophtheirus pollachii (Bassett-Smith), ' attached to the inside of the mouth of Pollack [Gadus pollachius), caught on the off- shore stations between Lancashire and Isle of Man ' ; L. pectoralis (O. F. Miiller), of which a very elaborate study has been made by Mr. A. Scott, using chiefly specimens from flounders {Pleuronectes fiesus) in the Piel fish- hatchery.^ To the above must no doubt be added Z#. salmonis (Kroyer), more commonly called L. stromii (Baird), the ordinary parasite of the salmon. In the family Dichelestiids the county no doubt also occasionally harbours Dichelestium sturionis (Hermann), parasitic on the sturgeons, for which Dr. Leigh vouches as part of the marine fauna. In the same family is included the species recorded by Mr. Scott as Cycnus pallidus (van Beneden), 'on the gills of the Conger {Conger vulgaris^, caught in the Barrow Channel.' The name Cycnus, however, is preoccupied, so that this species should now be called Congericola pallidus (van Beneden).* In the Lernasidae, Mr. A. Scott has carefully studied Lerncea branchialis (Linn.), of which he says: 'The adult female is found on the gills of the Gadidae, such as cod, haddock, and whiting. Immature (cyclops stage) males, and females with adult males attached, are found on the apex of the gill filaments of the flounder, sometimes in large numbers. Full-grown females are not plentiful on the fishes caught in the vicinity of Piel. The length of a full-grown female herncea is a little 1 Proc. Zool. Sac. Lond. pp. 438-507 (1899). 3 T;rans. Llverp. Biol. Soc. xv. 349 (1901), when not otherwise mentioned the remaining quotations are from this paper. 3 Op. cit. XV. p. 188. See also Thompson in op. cit. ix. 102.
 * Stebbing, in ffUky's Zoological Resu/is, pt. v. 672 (1900).