KCHINOIDKA. II. 



part of the Challenger -Report that I considered some young specimens from Stations 184 and 219 

 as perhaps not belonging to A(sthenosoma) gracilis. I am corrected for not repeating this every time 

 I mention A. gracilis ! (Op. cit. p. 84) and (Having made that statement (on A. gracile) 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 have no donbt that in the mass of 

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

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

 donbt was usually indicated on the labels accompanying them, but Dr. Mortensen has no words to 

 express his horror at snch a proceeding (Op. cit. p. 85). In the place to which Professor Agassiz 

 refers here ( Ingolf -Ech. p. 57) 1 have said: on the label was found a point of interrogation but of 

 this doubt nothing is said in the text and St. 272 is given without any reservation as a localitv of 

 Phormosoma tenue . That is all. - - It is really too bad to credit me with such folly as to object to 

 the marking of one's doubt 011 the labels when the identification of the specimens remains doubtful 

 — a thing which every careful student of Echinoderms knows will occur now and then, especiallv 

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

 proaching Professor Agassiz for doing this, but I do think that, when the identification is doubtful, 

 some donbt should be indicated in giving the localities of the species. I hope Professor Agassiz 

 will pardon me if I venture on a few instances: 



Asthenosoma gracile. On p. 90 (Challenger -Echiuoidea) is written: small specimens of Asthe- 

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

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

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

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

 tli is 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 examine a specimen ( A. gracile?) 

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

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

 thus appears that the original identification of this specimen 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 really is uncertain or even, as Professor Agassiz now admits, quite erroneous, 

 the species A. gracile 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 fathoms, whereas the species was at 

 that time really known onlv 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 really 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 

 1 1400 fathoms), 219 (150 fathoms) without any reservation. Any student of geographical distribution 

 would naturally conclude from these statements that the bathymetrical distribution of A. gracile has 

 been shown by Professor Agassiz in the Challenger Echinoidea to be from 150 1400 fathoms, 

 for it can scarcely be expected of such students that they should study the descriptions of all the 



