54 STABILITY OF THE (iKNKKA. 



among themselves like those of the Amphioxus and of 

 sr//m'//s. between which imaginary evolution has worked, 

 according to theory, in nearly the same period of time. 



But the material facts discovered by palaeontology and 

 accessible to everyone, dispel all illusion. In effect, the 

 Naut Hides, notwithstanding the great number of their 

 specific forms, which must exceed .'>()(), depart so little from 

 their initial typo, throughout the geological ages, that the 

 merest novice would not hesitate in any case to recogni/e 

 their generic nature. The variations or differences among 

 the species, oscillate without any tendency to continue in a 

 single direction so as to found a new typo. In the actual 

 fauna, Nautilus does not show, between its forms and the 

 primitive forms, any greater differences than those which all 

 naturalists agree in considering as purely specific. Kven the 

 Triassie Xantilides show less affinity to existing species than 

 do the primitive forms. The theoretical evolution of the 

 cephalopods, like that of the Trilobites, appears to us to be 

 imaginary, without any foundation in fact.* 

 Dr. Paul Fischer, in a notice of Barrando's work, whilst 

 acknowledging the strength of the facts and observations brought 

 forward by that distinguished palaeontologist against the de- 

 velopment theory, does no! consider them conclusive: "The 

 iypc (Joniatites. says M . Fischer, has always been considered by 

 evolutionists as a natural transition beiween the Xamilns with 

 its very simple pariiiions and the foliaceons sutures of the 

 Ammonite; an opinion which is strengthened bv the appear- 

 ance of (Joniatites chronologically intermediate between the 

 other two. In order to show the extreme difference which 

 exists bciween ihc Nautilus and the (Joniatites. M . Barrandc 

 has studied the characters of the initial shell in these i wo genera 

 a study which has acquired great import-nice since the publi- 

 cation of Mr. Alphens Myaii's Fossil ( Yphalopoda." 



Mr. Hyatt has shown that the initial chamber of A'// /////.< 

 /'iHiijiiliiitt shows an elongated nearly linear cicat rice, enclosed 

 by an elliptical sin-face slightly depressed. He supposes that 

 the nvisack was attached to the elliptic surface, and that the 



<;,'nrrulrs/- \!'M-'j:,0, is;:. 



