STRONGrLOCENTROTUS. 155 



made cf a well-grown specimen from Hardangerfjord, as the Col- 

 lection contains but few specimens and all small. According to 

 Sars this species is very rare. It has been sometimes thought to he 

 a variety of E. norvegicus ; with the small number at my disposal 

 I am quite able to see the points of difference. 



Distribution. Both sides of Atlantic ; Mediterranean ; Admiralty 

 Islands. Down to 1350 fms. 



a-d. St. 47 a *. ' Porcupine Exp.,' 1868. 



e-h. S.W. Ireland, 250 fms. ' Flying Fox ' Exp. 



i,j. 54 miles off Achill Head, 500 fms. Royal Dublin Society. 



k, I. 45 miles off Blackrock, 500 fms. Royal Dublin Society. 



Echinus melo, Lamk. 



I cannot inscribe this species in the list of British specimens on the present 

 record ; Forbes (Rep. Brit. Assoc. 1850 (1851), p. 123) speaks of an Echinus 

 which " appears to be identical with the Echinus melo of the Mediterranean," 

 as having been found by Mr. Peach on the coast of Cornwall. In his ' Revision ' 

 Prof. Alex. Agassiz makes no reference to this, but in the Proc. Roy. Soc. 

 Edinb. xi. (1882), p. 697, he reports E. melo from off North Rona, after saying 

 " there is nothing new." 



2. STR0NGYL0CENTR0TUS, 



Echinus (pars), O. F. Midler, Prod. Zool. Dan. (1776) p. 235 ; Molina, 



Stor. not. Chili, (1782) p. 348. 

 Echinus (Toxopneustes) (pars), Ag. 8f Des. Ann. Sci. Nat. vi. (1846) 



p. 367. 

 Strongylocentrotu8, Brandt, Prodr. descr. Anim. (1835) p. 63; Gray, 



Proc. Zool. Soc. 1855, p. 37 ; A Agass. Bev. Ech. (1872) pp. 161 & 



276 ; Carus, Prod. Faun. Med. (1884) p. 99 ; Duncan, J. Linn. Soc. 



xxiii. (1889) p. 121. 

 Heliocidaris (pars), Ag. fy Des. Ann. Sci. Nat. vi. (1846) p. 371. 

 Echinometra, Gray, Brit. Bad. (1848) p. 4. 

 Loxechinus, Desor, Si/71. Ech. fuss. (1858) p. 136. 

 Psammechinus (pars), Dvj. <§■ Hup. Ech. (1862) p. 525. 

 Sphserechinus (pars), iid. t. c. p. 529. 

 Anthocidaris, Lutk. Vid. Medd. 1863 (1864), p. 1G4. 

 Euryechinus, Verri/l, Proc. Bost. Soc. Nat. Hist. x. (1866) p. 341. 



An echinine Echinid in which the secondary plates are formed of 

 more than three primary plates. Test circular or subpentagonal ; 

 gill-slits well marked. 



Key to the Species. 



Primary spines hardly larger than secondaries .... \. S. droebachiensis. 

 Primary spines distinctly larger than secondaries. . 2. & lividus. 



* No Station " 47 a " is given in the Report of the Voyage published in the 

 Proc. Roy. Soc. 18(59-70; Stat. 47 was at 59° 34' N., 7° 18' W., depth 

 542 fms. 



