STRONGYLOCENTROTTTS. 157 



Toxopneustes dubeni, Dvj.fyHupe, Hist. Nat. Echin. (1862) p. 532. 

 Toxopneustes carnosus, Al. Ag. Proc. A. N. S. Philad. (1853) 



p. 357. 

 Toxopneustes pictus, Norm. Rep. Brit. Assoc. 1868 (1869), p. 314. 

 Toxopneustes pallidus, G. 0. Sars, Fork. Vid.-Selsk. Christ. 1871, 



p. 25. 

 Toxopneustes droebachiensis, Loven, Vet.-Akad. Hdlg. xi. no. 7 (1874) 



pi. xvii. 



Test never large. Primary spines rather short, numerous, rather 

 sharp, white, brick-red, bright red, purple, yellowish green, or green 

 throughout, or with the tip lighter or darker than the rest. Secondary 

 spines numerous, not obscured by the primaries ; pedicellariae 

 numerous. 



Test pentagonal in outline, rather depressed ; pretty stout, with 

 twenty prominent rows of primary tubercles, large peristome ; 

 calycinal area compact, prominent madreporite, moderate periproct. 



About fourteen plates in each interambulacral series, those at the 

 ambitus twice as wide as deep, with a single large primary tubercle 

 occupying the middle of the plate ; on either side there is a smaller 

 primary tubercle, and on the outer side there are sometimes two, 

 one above the other ; these are larger and more definitely arranged 

 below and at than above the ambitus ; the rest of the plate is occupied 

 by smaller miliary tubercles. The primaries of the ambulacral 

 plates are somewhat smaller than those of the interambulacral, but 

 the primary tubercle which occupies the middle of each plate is 

 quite distinct ; between the two rows are a few miliaries, and in the 

 midst of each arc there is one small tubercle, occasionally there are 

 two, and very rarely there are three. 



Distribution. Circumpolar, extending as far south as north coast 

 of France, Massachusetts Bay, Vancouver's Island, Sea of Okhotsk. 

 0-640 fms. 



a. Shetland. E. Forbes, Esq. 



b. Sandwich Bay, Shetland. E. M. Nelson, Esq. 



c. Cromarty Frith. Dr. A. Sutherland. 

 d-x. Montrose. W. Duncan, Esq. 



2. Strongyloceirtrotus lividus. 



Echinus lividus, Lamk. An. s. Vert. in. (1816) p. 50 ; de Bl. Diet. 

 Set. Nat. xxxvii. (1825) p. 88; Desmoulim, Syn. Ech. (1837) 

 p. 282 ; Forbes, Brit. Star/. (1841) p. 167 ; Valentin. Anat. Echin. 

 (1841) p. 1; Cuvier (Masson's ed.), pi. 11. figs. 2-4; J. Muller, 

 Abh. Ah. Berl. 1850 (1852), p. 49, with numerous figs, of larva?, as 

 also in Metschnikoff, Mem. Ac. St. Petersb. xiv. (1869) no. 8, pis. vii. 

 & viii. ; Thompson, Nat. Hist. Irel. iv. (1856 ) p. 441 ; Cailliaud, 

 Cat. Bad. Loire. Inf. (1865) p. 21 ; John, Arch. f. Nat. Iv. (1889) 

 pp. 299-301 ; Few'kes, Amer. Nat. xxiv. (1890) p. 1. 



Echinus lithophagus, Leach, Tilloch's Phil. Mag. xxxix. (1812) 

 p. 151 ; id. Mem. Wern. Soc. ii. (1818) p. 647. 



Echinus sp., E. T. Bennett, Trans. Linn. Soc. xv. (1827) p. 74. 



Echinus (Toxopneustes) lividus, Ag. fy Des. Ann. Sci. Nat. vi. (1846) 

 p. 367. 



