BCHINOIDEA. II 



a-~ possible all the structures known to be of classificatory importance, and Professor A gas si z will, I hope, 

 recognize that I have done my duty in this respect. If I have characterised some new species mainly 

 by the structure of their pedicellaria;, this is due to the fact that the specimens, being in the posses- 

 sion of foreign museums, were not at my full disposal. Moreover, I have established such new species 

 only when convinced of having made known sufficient characters for their certain recognition. It does, 

 however, seem to me that any method which enables one to determine the species of a rare specimen 

 without destroying or damaging it, is to be welcomed. Such a method is presented in main cases, 

 though certainly not in all, by the study of the pedicellariae; if by adopting this method we can pre- 

 serve some beautiful or rare specimen undamaged in a Museum, surely the destruction of such a speci- 

 men would be regrettable. Hence I have cited with approbation the remark of Stewart: that we 

 may be enabled by the examination of even an ambulacra! tube or pedicellaria etc. to determine a 

 species without denudation of portions of the corona, which is sometimes not desirable . Apart from 

 this, even Professor Agassiz will agree, surely, that one may lament the loss of tvpe-specimens 

 of several of the insufficiently described species of older authors without being stigmatised as childish ; 

 but I have never lamented the loss of specimens due to the necessary examination of the test; indeed 

 I fail to see, why the removal of a few spines from the test should involve the loss of the specimen. 

 Possibly Professor Agassiz has interpreted my occasional use of the word destroy to mean loss, thou gh 

 my intention was to allude only to the destruction of the beautiful appearance of the specimens. — 

 For the rest, I may refer to the remarks of Professor Ddderlein (Op. cit. p. 70) on this question, with 

 which I fully agree, deun (aueh) ich stehe auf denj Standpunkt. dass ich nur dann eine Art als geniigend 

 gekennzeichnet ansehe, wenn die alte Methode, die Beschreibung von Schale u. s. w. vereinigt ist mil 

 der neuen Methode der Beschreibuug der Pedicellarien u. s. w. 



I now come to the gravest accusation brought against me by Professor Agassiz, that of gratui- 

 tous misrepresentation of facts>. On p. 25 (Op. cit.) Professor Agassiz says: Dr. Mortensen names as 

 Dorocidaris micans specimens of a Cidaris which he received from the U. S. National Museum, Washing- 

 ton, labelled as Porocidaris Sharreri («Albatross 1885. St. 24151 and also from the U. S. Fish Commis- 

 sion (Albatross 1885. St. 2345) under the same name. I beg to call Dr. Mortensen's attention to the 

 fact that the publication of the «Blake Echini dates back to 1883, and that 1 was in no wav con- 

 cerned in making the collection of the Albatross in 1885, or with the identification of the Echinoids 

 then collected. Dr. Mortensen's statements ( Ingolf Echinoidea. pp. 22, 231 in regard to Porocidaris 

 Sharreri are gratuitous misrepresentations of facts . — My remarks on Porocidaris Sharreri run thus 

 (loc. cit): Agassiz unfortunately gives no details as to the pedicellarise, and from the figure (op. cit. 

 PI. Ill) it cannot be decided whether it is a genuine Porocidaris. There seems to be no highly deve- 

 loped neck on the spines (in the text nothing is said of this feature); the pedicellaria might well look 

 like those of P. pnrpurata, but a close examination will be necessary for the decision. By the kindness 

 of Prof. Rathbun I have from (the) l'. S. National Museum received a specimen determined as 

 P. Sharreri I Albatross 1875. St 2415); it proved to be the new species Stereocidaris ingolfiana de- 

 scribed hereafter; it has no relation to P. Sharreri. Further I have in (the) British Museum seen a speci- 

 men determined as P. Sharreri, from the U. S. Fish Commission (Albatross^ 1885. St. 2345). Neither 

 seems this specimen to be identical with the real, figured P. Sharreri, at all events it does not to 



The Ingolf-Expedition. IV. 2 7 



