"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 Polystomella 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 preservation of this colour seems to indicate that no considerable metamorphic 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 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 Cycloclypeus; and an ordinary want of completeness of separation between the chambers, corresponding with that which is characteristic of Carpenteria. "There is no other group of the animal kingdom to which Eozoon presents the slightest structural resemblance; and to the suggestion that it may have been of kin to Nullipore, I can offer the most distinct negative reply, having many years ago carefully studied the structure of that stony Alga, with which that of Eozoon has nothing whatever in common. "The objections which not unnaturally occur to those familiar with only the ordinary forms of Foraminifera, as to the admission of Eozoon into the series, do not appear to me of any force. These have reference in the first place to the great _size_ of the organism; and in the second, to its exceptional mode of growth.