HCHINOIDEA. II. 



part of the Challenger -Report that I considered some \onn!;;- speciuKiis from Stations i<S4 and 219 

 as perhaps not belonging- to A(stlirnosoma) gracilis. I am corrected for not repeating this ever\ time 

 I mention A. gracilis!. (Op. cit. p. 84) and Having made that statement (on A. gruciln I am taken 

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

 where else (Op. cit. p. 1051. — Again Professor Agassiz writes.: I have no doubt that in the ma.ss of 

 material collected bv the Challenger which passed through my hands I must have failed to distin- 

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

 doubt was usuaih' indicated on the labels accompanying them, but Dr. :\lortensen has no words to 

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

 refers here I Ingolf -Ech. p. 571 1 have said: on the label was found a point of interrogation but of 

 this doubt nothing is said in the te.xt and vSt. 272 is given without an\- reservation as a locaUty of 

 I'lioDiiosdiiiii Iriiiir . That is all. — It is really too bad to credit me with such foll\- as to object to 

 the marking of one's doubt on the labels when the identification of the .specimens remains doubtful 



a. thing which everx carefiil student of Echinoderms knows will occur now and then, especialh 



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

 proaching Professor Agassi/, for doing thi.s, but I do think that, when the identification is doubtful, 

 .some doubt should be indicated in giving the localities of the specie.s. I hope Profes.sor Agassiz 

 will pardon me if I venture on a few instances: 



Astlumosoiiia gracilr. On p. Qo ( Challenger -Echiuoideal is written: small specimens of .ij///*- 

 iiDSiiDiii from .Stations 184 and 219 are referred to this species with considerable dr)ubt ; on p. 91 are 

 named the following localities for A.gracilr: Stations 219, 200, 184 and 169. In \\\\ opinion .Stations 

 184 and 219 ought not to have been mentioned here at all, but, if the\ were to be mentioned, a note 

 of interrogation should certaiuh have been added. Again, it was incorrect to give Station 169 at 

 tliis place, as ma\ he seen from The Panamic Deep-Sea Echini p. 108, where Professor Agassiz 

 writes: Among the specimens left at Cambridge, I had occasion to examine a specimen 1 A.gracile?) 

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

 showing that it is not an .\sthenosoma but a new species of Phormosoma allieil to I'll, l/i.'ip/il/n// . It 

 thus appears that the original identification of this si)ecimeu was also doubtful though no hint 

 of this was given in the text. This apparently trivial point is really one of much importance. By 

 giving as certain what realK is uncertain or e\en, as Professor Agassiz now admit.s, quite erroneous, 

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

 Torres .Strait and East of New Zealand, at a depth of 150—1400 fathoms, wiiereas the species was at 

 that tinu' realh known onl\ from the Phili]ipines frcnn 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 Stations 169 (700 fathoms), 184 

 (1400 fathoms), 219 (150 fathoms! without any reservation. .\n\ student of geographical distribution 

 would naturally conclude from these statements that the bathymetrical distril)ution of .1. gracilc has 

 been .shown b> Professor Agassiz in the Challenger Echinoidca to be from 150 1400 fathoms, 

 for it can scarcely be expected of such students that the\ should stnd\ the descri})tions of all the 



