KCHINOIUEA. II. 



part of tlie Clialleno;er -Report that I considered sonie youiij^ speciiiieiis from Stations 184 and 219 

 as perhaps not belonging to A(stlic)iosoma) gracili.s. I am corrected for iiot repeatin« tliis e\er\' time 

 I niention A. gracilis!. (Op. cit. p. 84) and Having made that statement |on .i. gracilc) I am taken 

 to task by Dr. Mortensen for having made a statement in one place and not having repeated it some- 

 where else (Op. cit. p. 105). — Again Professor Agassiz writes: I liave no doubt that in the mass of 

 material collected b\- the Challenger whicli "passed through m\ hånds I mnst have failed to distin- 

 guish all the species. I was frequently in doubt as to the identification of certain specimens. That 

 doubt was usualh' iudicated on the labels accompanying them, but Dr. ^lorteusen has uo words to 

 e.xpress his horror at such a proceeding (Op. cit. p. 85). In the place to which Professor Agassiz 

 refers here ( Ingolf -Ech. p. 57) I have said: on the label was found a point of iuterrogation but of 

 tilis doubt uothing is said in the te.xt and St. 272 is given without au\ reservation as a localit\' of 

 PlinniiosdiiKi fru lir . That is all. - It is realh' too bad to credit uie with such folly as to object to 

 the uiarking of one's doubt on the labels wheu the identification of the specimens remains donbtful 

 — a thing which every careful student of Echinoderms knows will occiu' now and then, especialh' 

 when the material is not in the best state of preservation. Of conrse I have never thought of re- 

 proaching Professor Agassiz for doing this, but I do think that, wlien the identification is donbtful, 

 some doubt should be iudicated in giviug the localities of the species. I hope Professor Agassiz 

 will pardon me if I \enture ou a few iustances: 



Asfhriiosoina gracilc . Ou p. 9<i (Challenger -Echinoidea I is written : small specimens of .Ja/Z/c- 

 iiosdiiia from Stations 184 and 219 are referred to this species with considerable doubt ; on p. 91 are 

 named the following localities for ^l. gracilc: Stations 219, 2cx3, 184 and 169. In my opinion Stations 

 184 and 219 oxight not to have been mentioned here at all, but, if the\ were to lie mentioued, a note 

 of iuterrogation should certainh- have been added. Again, it was iucorrect to gi\e Station 169 at 

 this place, as may be seen from The Panamic Deep-Sea Echini p. 108, where Professor Agassiz 

 writes: Among the specimens left at Cambridge, I had occasion to e.xamiue a specimen ( A. gracilc ?} 

 from Challenger Station 169, and am able to give some details and figures of this .specimen, plainly 

 showing that it is not an Astheuosouia but a new species of Phormosoma allied to Ph. Iiispidiim . It 

 thus appears that the original identification of this specimen was also donbtful though uo hint 

 of this was given in the text. This apparenth trivial point is really one of uuich importance. B\- 

 gi\ing as certain what really is uncertain or even, as Professor Agassiz now admits, qnite erroneous, 

 the species A. gracilc has been stated to occur at the Philippines, the Admiralty Islands, East of 

 Torres Strait and East of New Zealand, at a depth of 150 — 1400 fathoras, whereas the species was at 

 that time realh knowu only from the Philippines from a depth of 255 fathoms. (Such erroneous state- 

 ments are not excused even if it be found later that the species realh' occurs in such localities and 

 depths.) In the lists concluding the Challenger Report the bathymetrical distribution of this species 

 is said on p. 210 to be 150—255 fathoms, while on p. 268 are named vStations 169 (700 fathoms), 184 

 (1400 fathoms), 219 (150 fathoms) without any reservation. Any student of geographical distribution 

 would natnrallx conclnde from these statements that the bath\metrical distribution of A. gracilc has 

 been showu by Professor Agassiz iu the Challenger Echinoidea to be from 150-1400 fathoms, 

 r it eau scarceh be expected of such students that the\- should study the descriptions of all the 



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