638 



REPOKT OF NATIONAL MUSEUM, 1904. 



the supposed organism to the group of Rhyzopods of the order of 

 foraminifera, and conceived that during life they were sessile by a 

 broad base and "grew by the addition of successive layers of cham- 

 bers separated by calcareous lamina? but communicating with each 

 other b} r canals or septal orifices sparsely and irregularly distributed." 

 He imagined, further, that the organisms grew in groups which ulti- 

 mately coalesced and formed large masses penetrated Ity deep, irregu- 

 lar canals and that they continued to grow at the surface while the 

 lower parts became dead and filled up with the infiltrated matter or 

 sediment, assuming the aspect of a coral reef. 



On account of their geological position, he proposed to designate 

 the animals b} r the name of Eozoon, and these particular ones by the 

 specific name of canadense, and in his annual address before the 

 Natural History Society of Canada for that year, referred to the dis- 



Fig. Vl~.— Portion of Eozoon magnified 100 diameters, showing the original cell-wall with tubulation 

 and the supplemental skeleton with canals, a, Original tubulated wall or "Numniuline layer;" 

 more magnified in Fig. A; 6 c, intermediate skeleton with canals. (After W. B. Carpenter.) 



covery as "one of the brightest gems in the scientific crown of the 

 Geological Survey of Canada." 



The paper by Dawson was immediately followed by one bj T the well- 

 known microscopist, W. B. Carpenter, whose conclusions were in 

 every way confirmatory of those of Dawson. To quote his own words: 



That the Eozoon finds its proper place in the foraminiferal series, I conceive to 

 be conclusively proved by its accordance with the great types of that series in all the 

 essential characters of organization, namely, the structure of the shell forming the 

 proper wall of the chambers, in which it agrees precisely with Nummulina and its 

 allies; the presence of an intermediate skeleton and an elaborate canal system, the 

 disposition of which reminds us most of Calcarina; a mode of communication of the 

 chambers when they are most completely separated, which has its exact parallel in 

 Oyclocypeus; and an ordinary want of completeness of separation between the cham- 

 bers, corresponding with that which is characteristic of Carpentaria. 



