26 ECHIXOIDKA. 11. 



not tliink that any single character should be made the basis of a classification or that a distance of 

 even hundreds of miles of sea-bottom is sufficient evidence of specific distinctness (p. 167), I must 

 refer in answer to what has been said above (p. 10) against Professor Agassiz' characterizing my 

 classification as being based on a single character, and also to the above remarks on Professor de 

 Loriol's objections. As for taking e\en hundreds of miles of sea-bottom as sufficient evidence of 

 specific distinctness, I absolutely agree with Professor Bell, and I am sure he will be unable to point 

 out any of the species described by me as being based upon geographical distance alone. But, on the 

 other Ixand, I think Professor Bell will agree with me that great geographical and bathymetrical 

 distance ought alwa\s to make one careful in referring specimens to a species otherwise known only 

 from another region, and only to identify them with such species on finding after a careful study of 

 all available characters that they cannot be distinguished. 1, for my part, do recognize some species 

 of Echini as almost cosmopolitan in their distribution, e. g. Hemiastcr cxpergitiis (see also my remarks 

 on Echinocardiiim cdrdntuvi in this Parti, though I do not recognize Echinus jiorvrgicns as a cosmo- 

 politan specie.s, as it was made b}- Professor Agassiz. 



Professor Bell's remark that the present condition of the family Ecliiiiotlniridce «does not 

 warrant any addition tcj it that need not be made (p. 169I, does not seem to me quite warranted; at 

 least it seems to me that it is easy enough to refer the species to the genera as diagnosed by me 

 whereas it was extremely difficult indeed to distinguish between Phormosoma and AsthoiosnDia after the 

 old fashion. And when Professor Bell expresses the hope that Professor Agassiz by means of his 

 large collections will be able to give us a definite idea of the range and character of the variation 

 of the Echinofhurnio". I must say that, if the minute differences are not taken into consideration, I 

 fear the v-ariations will not be \er\" reliable. The generic value of characters foimd in pedicellarise 

 may, of course, be disputed; but we can be quite sure that specimens of the same species do not have 

 pedicellarise of ver>- different structure, so that these minute characters, so easih- seen with a very 

 little technical skill, should at all e\ents never be despised. 



Lambert' remarks: «Saus nier la \-aleur des caracteres fournis paz les organes caducs et mi- 

 croscopiques de I'Echinide, j'estime que leur nomenclature doit surtout etre fondee sur un ensemble 

 de caracteres obser\ables, aussi bien chez les fossiles que chez les \ivants, car la phylogenie est aussi 

 indispensable que I'cmbryogenie a I'exacte comprehension des formes actuelles. II ne faut pas appliquer 

 a des aniniaux inferieurs, dont les organes sont moins specialises, une methode qui pent etre excellente 

 pour des etres tres e\'olues et perfectionnes, mais qui, pour les P'chinides, fausse toutes les analogies 

 en placant dans des t.iniilks differentes des formes aussi voisines que Eoxechiniis et Strongyloccntrotiis . 

 que Parasalenia et Goiiiopygits . Vox the rest, he states that he agrees with .\gassiz in his views 

 on m> clas.sification. — The claim that the classification of Echini has to be founded on characters 

 also ob.servabk- in fossil forms is, so far as I can see, unscientific. It is (|uite nn])os.sible to sav a ])riori 

 which character will l)e of primary importance for cla.ssification. (July by a careful comparati\e exam- 

 ination of all the characters presented by the animals in question can it be decided on which of 

 these characters the cla.s.sifi cation has to be founded. When it is proved that sonu- organ wliicli can- 



' In .M. lid 11 1 1- fl A Til I- VI' 11 in: ]-'ossiles ik- la cote oriciilalc de Mailajfascar. Annaks iK- I'aleontologie. I. 1906. 

 P- 14 (56). 



