Bd. VI: 4) 
THE ECHINOIDEA. 
45 
given by both Lamarck and Blainville, that it was not the species called thus 
by Agassiz. The figures given by Valenciennes equally speak decidedly against 
the identity with Agassiz’ species (whether they really represent Lamarck’s species 
or another species (inage llanicus ?)). The result is then unquestionably that the spe- 
cies described and figured by AGASSIZ cannot rightly keep the name niargaritaceus; 
I propose to name it Sterechinus Agassizii. 
In »Stellérides, Ophiures et Echinides» de l’Expédit. antarctique Française» Koeh- 
LER, after reproaching me for the confusion which I have raised in this case in my 
»Ingolf» Echinoidea, describes as » Echinus niargaritaceus » a species which is quite 
different from both the nnargaritaceus » of AGASSIZ and from the species which I 
had taken to be this species (viz. Sterech. diadema). It is Sterechinus Neumayeri , 
as is stated by Prof. KOEHLER in his later work on the »Astéries, Ophiures et Echi- 
nides de l’Expédition antarct. nationale Ecossaise» p. 616. (I have myself had occa- 
sion to examine a pair of these specimens, kindly sent to me from Prof. KOEHLER.) 
At length all these species, » niargaritaceus », diadema , antarcticus , Neumayeri and 
horridus , were diagnosed and redescribed by DöDERLEIN (Op. cit.), to whom thus 
belongs the merit of having first cleared up this rather difficult case. 
The reasons for the erroneous determinations by myself and Prof. Koehler are, 
partly the scarcity of the material at disposal, partly the insufficient descriptions 
given in the »Revision of Echini» and in the »Hassler» Echini; scarcely other cha- 
racters are pointed out than such as distinguish the whole genus Sterechinus. The 
only figure given, PI. IL b of the »Hassler» Echini, is likewise quite insufficient for 
distinguishing this species from diadema and Neumayeri ; in fact, KOEHLER takes 
this figure as a proof of his species ( Neumayeri ) being the true » niargaritaceus », as 
I have taken it as a proof that my species ( diadema ) was that species. DöDERLEIN 
finds in this figure that all the ocular plates are excluded from the anal area (he 
wrongly writes »Apicalfeld», p. 218). I wonder how it is possible to see that on 
this figure; I am quite unable to distinguish more than three of the ocular plates, 
and these probably are excluded from the periproct, as also KOEHLER remarks 
(Expéd. antarct. Franc, p. 33). — (On the other hand, I find this figure, as also 
PI. III. figs. 4 and 5, to be inverted; this is indicated by the fact that the anal 
opening is here represented as lying to the left side, while, as is well known, 
it really lies to the right (off Ocular I), the animal being orientated after Lo- 
VËN’s plan.) 
In order to acquire full certainty of the identity of the specimens in hand with 
the species figured by AGASSIZ I sent one of the specimens to Professor H. LYMAN 
Clark asking him to do me the favour to compare it directly with the specimen 
figured in the »Hassler» Echini. He kindly informed me that he found it to be the 
same species. I also sent one specimen to Professor DÖDERLEIN, asking him to 
