492 ECHINUS GRACILIS. 



rather stout, varying in color from white almost to purple. Color of test 

 brick-red, or brownish and intermediate shades, with scrobicular circle set off 

 in light upon this. 



Norway ; English Channel. 



Echinus gracilis 



'.Ec/Unus gracilis A. Ac, 1869, Bull. M. C. Z., I. 

 (See Part II. p. 293.) 



PI. Vl'.f.e; PI VII. f. l-e. 



Straits of Florida ; St. Thomas. 



Echinus magellanicus 



\ Echinus magellanicus Phil., 1857, Wieg. Arch., I. 



Only small specimens of this species exist thus far in the Museum, unless 

 an Echinus of which Mr. H. Edwards sent a couple of tests from Australia, 

 should prove the adult of it; as, unfortunately, they do not come from New 

 Zealand, where E. Magellanicus is found, 1 have made the description from 

 the smaller specimens, awaiting further materials. The small specimens 

 recall in general aspect the Mediterranean E. microtuberculatus. Abactinal 

 system is very prominent ; test thin ; poriferous zone distinctly colored, 

 giving the dry test a handed appearance. There are only two principal 

 prominent rows of tubercles in the intcrambulacral space ; generally but 

 one ocular plate reaches the anal system, frequently all are excluded ; 

 genital plates thickly tuberculated near the anal ring with small second- 

 aries : poriferous zone very narrow. Coronal plates narrow, closely packed 

 with irregularly arranged small secondaries and miliaries. tending to form 

 irregular vertical lines in the median ambulacra! spaces; spines line, mod- 

 erately long ; actinal membrane smooth, nearly bare ; but few actinal lime- 

 stone plates. Color of the test light violet ; edge of poriferous zone white ; 

 spines violet, tipped with yellow. In younger specimens a regular orna- 

 mentation is formed by the miliaries arranged round the secondaries. The 

 actinostome is remarkably small, nearly round, with the slightest possible 

 notches. 



4.1 

 Patagonia ; Chili ; New Zealand. 



