56 TH. MORTENSEN, (Schwed. Südpolar-Exp. 



The species was taken by the Swedish South Polar Expedition at Station 3 

 (54° 43' S. 64 8' W. 36 m.), 4 specimens. Further the Swedish Fuegian Expedition, 

 1896, has taken i specimen in Stewart Harbour, 20 fms., 2 specimens in F"ortescue 

 Bay, 10 — 12 fms., on bottom with algre. 



The geographical distribution of the species is the Pacific Coast of South Ame- 

 rica, from Tierra del Fuego to Callao (and probably still farther north). On the 

 Atlantic Coast it is not known beyond the Magellan Strait. — F"rom other localities 

 it has only been recorded from the Philippines, with doubt, in >Revision of Echini» 

 p. 162, while in the »Challenger» Echinoidea p. 211 this locality is given without 

 reservation. That the species does not really occur at the Philippines can not be 

 doubted. 



The bathymetrical distribution appears to be very limited, as it is not known 

 from greater depths than 85 m. (»Challenger.^ Ech. St. 304 ^Strongylocentrotus gib- 

 bosus-i). It is thus evidently a strictly littoral species. 



The history of this species is rather intricate. Abbé Molina in his »Essai sur 

 l'histoire naturelle du Chili» (translated from Italian by M. Gruvel 1789*) gives a 

 very poor description of his two species. Echinus albus and niger (p. 175): sDans 

 le genre des oursins il faut d'abord distinguer les oursins blancs et les noirs. Les 

 blancs (Echinus albus) sont de forme globuleuse, et d'environ trois pouces de dia- 

 mètre, le têt et les piquants sont blancs; la substance intérieure, qui est d'un gout 

 excellent, est jaunâtre. Les oursins noirs (Echinus niger) sont de forme ovale, un 

 peu plus grands que les blancs, ils ont le têt, les piquants et les œufs noirs, et on 

 ne les mange pas. a In a note the following diagnoses are given. Ecli. albus: 

 »Echinus hemisphserico-globosus, ambulacris denis; areis longitudinaliter verrucosis;. 

 Ech. Jiiger: »Echinus ovatus, ambulacris quinis, areis muricatis verrucosis->. It might, 

 indeed, seem quite impossible to recognize from this description the two species now 

 identified as Molina's Echinus albus and niger, viz. Loxecliiniis albus and Tetra- 

 pygus niger; especially the former has neither the test nor the spines white, as said 

 by Molina. Nevertheless it does not appear that Molina's description could be 

 better applied to any other Echinoid commonly occurring at the coasts of Chili, so 

 it seems that the interpretation first given in the Catalogue raisonnée des Echinides» 

 by Ag.ASSIZ & Desor is correct. The correctness of this identification is also indi- 

 cated by the description of Echinus albus given (by Bl.\nch.\kd) in Gay's Historia 

 fisica y politica de Chile (loc. cit.): »E. hemisphaerico depresso, obscure pentagono, 



* The Itali.in Original work »Sciggio sulla storia naturali del Chili > 1782, I have not seen; but Dr 

 Hart.meyer in Berlin has kindly quoted the place for me, so that 1 have been able to compare it with 

 the translation. 



