1865.] CARPENTER — STRUCTURE OF EOZOON. 117 



It does not appear to me that the canal-system takes its 

 origin directly from the cavity of the chambers. On the contrary, 

 I believe that, as in Calcarina (which Dr. Dawson has correctly 

 referred to as presenting the nearest parallel to it among recent 

 Foraminifera), they originate in lacunar spaces on the outside of 

 the proper walls of the chambers, into which the tubuli of those 

 walls open externally ; and that the extensions of the sarcode-body 

 which occupied them were formed by the coalescence of the pseu- 

 dopodia issuing from those tubuli.* 



It seems to me worthy of special notice, that the canal-system , 

 wherever displayed in transparent sections, is distinguished by a 

 yellowish-brown coloration, so exactly resembling that which I have 

 observed in the canal-system of recent Foraminifera (as Polystom- 

 ella and Calcarina') in which there were remains of the sarcode- 

 body, that I cannot but believe the infiltrating mineral to have been 

 dyed by the remains of sarcode still existing in the canals of Eozoon 

 at the time of its consolidation. If this be the case, the preserva- 

 tion of this color seems to indicate that no considerable metamor- 

 phic action has been exerted upon the rock in which this fossil 

 occurs. And I should draw the same inference from the fact that 

 the organic structure of the shell is in many instances even more 

 completely preserved than it usually is in the Nummulites and 

 other Foraminifera of the Nummulitic limestone of the early 

 Tertiaries. 



To sum up, — That the Eozoon finds its proper place in the For- 

 aminiferal series, I conceive to be conclusively proved by its accor- 

 dance with the great types of that series, in all the essential charac- 

 ters 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 skele- 

 ton 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 Cycloclypeus ; and an ordinary want of complete- 

 ness of separation between the chambers, corresponding with that 

 which is characteristic of Carpentaria. 



There is no other group of the Animal Kingdom to which Eozoon 

 presents the slightest structural resemblance ; and to the sugges- 

 tion that it may have been of kin to Nullipore, I can offer the most 

 distinct negative reply, having many years ago carefully studied 



* Op. cit.j p. 221. 



