A HISTORY OF LANCASHIRE carry with their variations and abnormalities proportionate difficulties of description and classification. Writing in 1893 Mr. Thompson entered in his list Lichomolgus agilis (Scott), remarking, 'This species was recently described by Scott {Ann. and Mag. of Nat. Hist., Sept., 1892), who found it plentiful in the shell of the cockle {Cardium edule) in specimens from Morecambe, Lancashire, and from the Firth of Forth. Upon examining fresh cockles of our district, I find several specimens of this active little Copepod in every bivalve opened. They may be readily found by carefully taking up the water contained in the shell by means of a camelhair brush and washing it into water contained in a watchglass under the microscope, when they will probably be seen actively darting about.' ^ In a later volume, how- ever, Mr. Thompson reported that '■Lichomolgus [Doridicola) agilis (Leydig) was found in the bottom of a tow-net, Morecambe Bay, May, 1894,' and in a subsequent reference to the occurrence of this species in another locality he observes, ' This is not the Lichomolgus agilis of T. and A. Scott referred to in the First Report as having been found in the cockles. The latter species is identical with Hermanella rostrata (Canu), a species which was described and published a short time before the figures and description by T. and A. Scott appeared.'* Canu's genus was apparently spelt Hermannella in 1891, and certainly Herrmannella in 1892, not Hermanella as Thompson writes it. Of Lichomolgus hirsutipes (T. Scott) Thompson says, 'This well-marked species was obtained from collections made in the Zostera beds near Piel ' ; of Hersiliodes littoralis (T. Scott), that it ' occurred sparingly in gatherings made on the mud flats near Piel ' ; and of Nicothoe astaci (Audouin and Milne- Edwards), that this 'peculiar parasitic Copepod, which has all its appendages fully developed, is found occasionally in considerable numbers on the branchiae of the common lobster caught on our coasts ; we have noted its occurrence on lobsters from Holyhead, Port Erin, and Piel ; the wing-like projections of the fourth thoracic segment give it an unusual appearance.' * It may be looked upon as the familiar spirit of the lobster ; and those who would deprive the lobster of its proper generic name Astacus, commit an outrage upon the old-standing designation of this interesting little entomostracan, its attached companion. Mr. Andrew Scott records Modiolicola insignis, Aurivillius, living as a messmate within the mouth of the ' horse mussel,' Mytilus modiolus. He relates that ' a number of specimens were found in the examples of this Mollusc which were brought up in the trawl-net of the steamer while working in the vicinity of the north end of " the Hole," on March 23rd, 1895,' and adds that ' this appears to be a widely distributed species of Copepod, its range being probably co-extensive with that of the Mollusc' As he assigns the species to the family Sapphirinidce, Thorell, it may be convenient to notice that Canu places it along with Lichomolgus and Herrmannella in the Lichomolgids, allotting Hersiliodes and Nicothoe to the Hersiliidae * (now preferably known as Clausidiids). Giesbrecht thinks that the perplexing Nicothoe might find rest in a sub-family of its own among the Asterocheridae.^ In the family Ascomyzontidx, A. Scott in 1896 described the new species Ascomyzon thompsoni, first obtained off the Isle of Man, but of which he says : 1 Loc. cit. p. 207. s Op. cit. ix. pp. 102, 160. s Loc. cit. p. 14.3. * Les Cop'epodes du Boulonnais, pp. 238, 248 (1892). 5 Fauna und Fbra des Golfcs von Neapel, Mon. 25, p. 57 (1899).
