ARCTIC SEA TO THE WEST OF GREENLAND, 19 



ECHINOIDEA. 



ONE solitary species of Echinus is the sole representative of this large class in the 

 Smith-Sound area ; no other Echinoid passes in this direction from the North Atlantic 

 up Davis Straits beyond the Arctic Circle. The form in question, Strongylocentrotus 

 drobachiensis, would, indeed, seem to hold undisputed sway in the boreal regions, being 

 essentially and unequivocally circumpolar in its distribution, as will be seen from the 

 list of localities appended below. Considerable variation is manifest, as might naturally 

 be expected in so wide a range ; but the stages are so gradual and the intermediate 

 forms so constantly maintained, that no characters of specific value are recognizable 

 amongst them ; and we are, in this instance, presented with an interesting example of 

 a species modified under the influence of various conditions of existence (habitat) alone, 

 without the cooperation or hostile action of any closely allied competitive forms. 



STRONGYLOCENTKOTUS DROBACHIENSIS (Miiller), A. Agassiz, Plate II. Figs. 1-3. 



1776. Echinus drobachiensis, 0. F. Miiller, Zool. Dan. Prodr. p. 235. no. 2846. 



1780. Echinus saxatilis, Fabricius (non Miiller), Fauna Groenlandica, p. 372. no. 368. 



1788. Echinus drobachiensis, Gmelin, Syst. Nat. linn. ed. xiii. p. 3169. 



1816. Echinus neglectus, Lamarck, Anim. s. Vort. ed. i. vol. iii. p. 49. 



1826. Echinus granularis, Say (non Lamarck), Proc. Acad. Nat. Sci. Philad. 1826, p. 225. 



1828. Echinus subangularis, Fleming (non Leske), Hist. British Animals, p. 479. 



1835. Strongylocentrotus chlorocentrotus, Brandt, Prod. Descript. anim. ab Mertensio obs., faso. i. p. 264, 



1836. Echinus neglectus, Agassiz, Mem. Soc. So. Nat. Neufchatel, i. p. 190. 



1837. Echinus chlorocentrotus, Des Moulins, Etudes sur les Eehinides, p. 282, 



1840. Echinus granulatus, Gould, Invert, of Massachusetts, p. 344. 



1841. Echinus neglectus, Forbes, Hist. British Starfishes, p. 172. 



1844. Echinus neglectus, Diiben & Keren, K. Vet.-Akad. Handl. 1844, p. 277. 

 1846. Toxopneustes drobachiensis, Agassiz, Cat. rais., Ann. Sci. Nat. vi. p. 367. 

 1846. Toxopneustes neglectus, Agassiz, Cat. rais., Ann. Sci. Nat. vi. p. 367. 

 1846. Toxopneustes granulates, Agassiz, Cat. rais., Ann. Sci. Nat. vi. p. 368, 

 1846. Toxopneustes Dubenii, Agassiz, Cat. rais., Ann. Sci. Nat. vi. p. 368. 

 1848. Echinometra drobachiensis, Gray, British Eadiata of the Brit. Museum, p. 4. 



1851. Echinus neglectus, Brandt, Middendorff's Sibirische Eeise, Bd, ii. p. 34. 



1852. Echinus neglectus, Forbes, Sutherland's Journal of a Voyage &c. vol. ii. Append, p. ccxiv. 



1853. Echinus granulatus, Stimpson, Syn. Mar. Invert. Grand Manan, p. 15. 



1857. Toxopneustes drobachiensis, Liitken, Vid. Meddel. N. Forening i Kjobenhavn, 1857, p 24. 

 1857. Toxopneustes drobachiensis, Sars, Bidr. Middelhavete Littoral-Fauna, p. 115. 



1857. Echinus chloroticus, Stimpson, Journ. Bost. Soc. Nat. Hist. vi. p. 86. 



1858. Toxopneustes neglectus, Desor, Syn. des Echin. foss. p. 135. 



1863. Toxopneustes drobachiensis, A. Agassiz, Proceed. Boston Soc. Nat. Hist. 1863, p. 191. 



1863. Toxopneustes carnosus, Barnard, in Agassiz, Proc. A. N. S. Philad. 1863, p. 357. 



1863. Toxopneustes chlorocentrotus, Liitken, Vid. Meddel. N. Forening i Kjobenhavn, 1863, p. 144. 



1863. Toxopneustes granulatus, Liitken, Vid. Meddel. N. Forening i Kjobenhavn, 1863, pp. 144, 148. 



1866. Eury echinus drobachiensis, Verrill, Proceed. Boston Soc. Nat. Hist. vol. x. pp. 341, 352. 



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