1880.] OF CERTAIN ECHINOIDEA. 221 



telles (Introduction).' I have only followed their example and 

 that of Prof. Agassiz himself." 



If by this Mr. Alexander Agassiz only means that those who do 

 not quote it as the second livraison, quote it by its titlepage, I 

 submit that such an answer is a mere trifling with the Zoological 

 Society ; but if he means that such is the ordinary method of re- 

 ferring to the ' Observations' &c., (and that he does mean or aim at 

 meaning this is probable from his preceding statement that Prof. 

 Louis Agassiz " invariably spoke of it as ' 1' Introduction de la Mono- 

 graphic des Scutelles' ") I can pass to 



(2) The mode of reference adopted by other loriters. Mr. Alex- 

 ander Agassiz states that his father invariably spoke of it in one 

 way ; of course, as an answer, Mr. Agassiz means that there are printed 

 references to the ' Observations . . .' in which the abbreviation 

 adopted by himself in his ' Revision' is used. There may be such, 

 but I am not acquainted with them, although I can point to five 

 genera in the ' Nomenclator ' in which a different method o^ reference 

 is adopted. Let the reader turn to Amblypneustes, Pleurechinus, 

 Temnopleurus, Agarites, or Tetrapygus, and he will "invariably" find 

 succeeding these names the expression " Agass. IMonogr. Echin. 2de livr. 

 1841." Turning now to other witnesses, I will call on two honoured 

 names : one was, with Louis Agassiz, the author of the ' Catalogue 

 Raisonne,' and he ' writes Monogr. d'Echinodermes, 2e livre. p. 7 ; 

 the other is Alex. Agassiz's eminent compatriot A. E, Verrill, who 

 (s. V. Euryechinus) writes, on p. 304 of his ' Notes on the Radiata in 

 the Museum of Yale College' (1867), "Agassiz, Monogr. d'Echinod. 

 2mehvr. (Introduction), July 1841." 



It is of no use to appeal to the 'Catalogue Raisonne '(1846, 1847), 

 for the essay in question is not there referred to ; nor is there, to my 

 knowledge, any reference to it in such considerable authors asLiitken'^, 

 Von Martens, Perrier, or Dujardin and Hupe'. The Society will now 

 see how far Prof Agassiz is justified in his term " all," and in his 

 adverb "invariably." 



(3) Contents of the " Essay. '^ Even now I am not certain that 

 Mr. Alex. Agassiz and I are referring to the same paper. It is true 

 that we both refer to an article published under the same cover as 

 the Monograph of the Scutellidse, that we both quote the title 

 ('Observations . . .') in just the same way, and that we both find on 

 a given page just the same generic names ; and yet we differ com- 

 pletely as to its other contents and as to its aim. The basis of my 

 contention obviously laid in the fact that I looked upon the ' Ob- 

 servations ' as having a general interest, and as being, therefore, in- 

 correctly denominated by the term " Int. Mon. Scut." ; we learn 

 now, however, from unquestionable authority, that "the contents of 

 this so-called essay, in spite of the heading, show plainly enough 

 that it was not considered at the time as a special essay, but that it 

 was simply an Introduction to the Livraison." Now is the rest of 



^ Desor, ' Synopsis des Echinides fossiles,' p. 113. 



^ Save this, " 1841 opstillede Agassiz (Preface) imidlerted en Hsekke af 

 Slaegter . . ." (Vidensk. Meddel. 1864, p. 154). 



