Page:VCH Cornwall 1.djvu/337

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CRUSTACEANS Falmouth,' 1 and Metridia armata, Boeck, of which he says, ' I have myself taken it, though very sparingly, in the surface-net amongst the Scilly Islands.' 2 Giesbrecht and Schmeil, however, identify this species with the earlier M. Jucens, Boeck. 3 In the Candaciidae, Brady says of his own f Candace pectinata,' ' a very few specimens of this interesting species were dredged by Mr. Robert- son and myself in June, 1873, on very hard ground, and in a depth of about 40 fathoms, south-west of the island of St. Agnes, Scilly.' 4 The generic name is more properly Candada (Dana). The family Pontellidae is represented by Parapontella brevicornis (Lubbock), which Brady found among Algae and Zostera at the Scilly Islands, 5 and from Falmouth, Vallentin reports Dias /ongiremis, Lillejeborg, and Pontella wollastoni, Lubbock ; the former now known as Acartia /ongiremis, the latter as Labidocera wollastoni. Here also occurs the widely and profusely distributed, the brilliantly and variously coloured, little Anomalocera patenonii, Templeton. Under the heading ' Pelagic Cope- poda,' Vallentin says, ' Considering the important part played by these forms in serving as food to many fish during their larval or adult conditions, it is astounding that more attention has not been given to them by Falmouth naturalists. With the exception of one record of the capture of Anomalocera patersonii, Temp. . . .,' as procured by Dr. Vigurs in his tow-net, August, 1850, ' I have been unable to discover a single reference to any of the marine pelagic copepods occurring at Falmouth.' Cocks, however, must be added to the recorders, since in 1857 ^ e re P r ts it as found ' in water from harbour ; ponds on rocks, Gwyllyn-vase. Taken by Dr. Vigurs in his tow-net, harbour, etc.' The Podoplea, copepods ' that have feet on the pleon,' are named from the circumstance that the fifth thoracic segment seems to have deserted the thorax for an alliance with the pleon, to which it commonly contributes a pair of feet. The families are numerous, and not to be understood without careful study. The most familiar is the Cyclopidae, in which the genus Cyclops is said to contain no species that can be relied on as being exclusively marine. Cocks gives C. quadricornis, Linn., from ' Water-tank and pond, near Mr. Jago's farm house.' More than one species was named quadrtcornis by Jurine, and which of them is here intended remains obscure. Brady took C. vicinus, Uljanin, from pond at Tresco (Scilly), and at first named it C. pulchet/us, Koch. 6 From the same locality he obtained C. fimbriatus y Fischer, at first naming it C. crassicornis, O. F. M. 7 The specimens from Tresco and other places on which he founded C. hel/eri having all been lost, Brady thinks it ' best for the present to regard the species as one of doubtful validity.' 8 C. aequoreus, Fischer, he found at St. Mary's (Scilly), and regards it as ' probably a pretty common inhabitant of the brackish pools of salt marshes.' 9 Cyclopina /ittoralis, Brady, was obtained by that author ' amongst the Scilly Islands in 14 fathoms.' 10 Oithona spinirostris, Claus, belonging to a genus exclusively marine, is recorded by Vallentin from Falmouth. In the family Arpacticidae the cephalothorax is not strongly distinguished from the pleon. In the wide sense this is an enormous group. For convenience it has been broken up into several subor- dinate families or sub-families. To the Longipediidae belong Longipedla scotti, Sars, called L. coronata, Claus, by Brady, who found it ' off St. Mary and St. Agnes, Scilly Islands ' ; n Ectinosoma sanii, Boeck, called E. spinipes by Brady, from ' Scilly Islands, IO to 40 fathoms ' ; 12 E. melaniceps, Boeck, found ' sparingly amongst weeds near low-water mark at St. Mary's, Scilly ' ; 13 and Bradya typica, Boeck, ' taken off Porcressa Bay (Scilly Islands) in a depth of 20 fathoms.' 14 To the Tachidiidae, Brady assigns Tachidius brevicornis (O. F. M.), from ' pond at St. Mary's, Scilly Islands,' 16 and Euterpe graci/is, Claus, recorded by Vallentin from Falmouth, and by Giesbrecht identified with the earlier Euterpina acutifrons (Dana). 16 The Stenheliidae are represented by Stenhelia ima, Brady, from St. Mary's, Scilly, 17 5. pygmaea, Norman and Scott, near Eddystone ; S. varians, Norman and Scott, outside Fowey, Parastenhelia ang/ica, Norman and Scott, from the same locality, and Daniehsenia fusiform'u (Brady and Robertson), which ' occurred plentifully in a dredging made off Porcressa Bay, Scilly, in 2O fathoms, on a bottom of hard sand.' 18 The Canthocampidae have in the title genus Canthocampus (Westwood), C. palustris, Brady, ' taken in a large pond, subject to occasional tidal influx, at St. Mary's (Scilly),' 19 and Cocks reports C. minutus, Baird, from ' water-butt, pond, etc.,' and_ C. stromii, Baird, from ' minute Algae, corallines, etc., ponds on rock, Gwyllyn-vase.' Of these two species Brady accepts the former as C. minutus (O. F. M.), but transfers the other to Dactylopus (Claus) (now Dacty/opusia, Norman). D. ornata and several other new copepoda have I Trans. Nat. Hist. Sue. Northumb. etc. (1891), vol. xi, pt. i, p. io5.

  • Monograph of British Copepoda, vol. i (1878), p. 44.

3 Mon. in Das Tierreick (1898), p. 106. 4 Man. Brit. Cop., vol. i, p. 50. 5 Ibid. p. 71. 6 Trans. Nat. Hist. Soc. Northumb. etc. (1891), vol. iv, pt. i, p. 78.

Ibid. p. 91. 8 Ibid. p. 92.

9 Mon. Brit. Cop. vol. :, izo. 10 Ibid. p. 93. II Ibid. vol. ii (1880), p. 8. " Ibid. p. 10. 13 Ibid. p. 12. " Ibid. p. 1 8. 15 Ibid. p. 22. 16 Pelagische Copepoden von Neapel (1892), Mon. 19, p. 555. 17 Mon. Brit. Cop. vol. ii, p. 36. l8 Ibid. p. 41. 19 Ibid. p. 54 285