144 Proceedings of the Royal Irish Academy. 
that the various " eozoonal features" are the product of chemical or 
pseudomorphic changes in serpentine, initiated by structural disinte- 
gration, to which it is characteristically liable ; and we have a legiti- 
mate right to use every evidence bearing out this view. Respecting the 
fossil wood" illustration, the ^' disintegrated portions" of the case 
are totally without analogy ; since, obviously, they do not initiate the 
''minute structures" alluded to. IN'one of the arguments, or facts, 
we have brought forward to support our theory were derived from 
the examples of ''Eozoon compressed, crushed, or partly destroyed by 
mineralization." 
10th. "We may be allowed to ask the reader to compare our de- 
tailed description of the grains of coccolite, and the mineral configu- 
rations, occurring in the Aker crystalline limestone, with Dr. Dawson's 
mode of putting ''objections" and "reasons" against them, to show 
that we have not been met in a way consistent with what is recog- 
nised in a scientific controversy. 
11th. We fully expected when the occarrence of a "perfect canal 
system preserved in malacolite," and occupying the crevices in a crystal 
of spinel, from Amity, New York;, became known to Dr. Dawson, that he 
would have procured specimens of the spineliferous rock at once. As this 
has not been done, and as there is nothing in the Paper under criticism 
to controvert this " remarkable case," we may assume it as completely 
demonstrative of the mineral origin of "Eozoon."| 
12th. Dr. Dawson has "never been able to satisfy himself of the 
occurrence of any definite organic structure in the Connemara speci- 
mens of ophite moreover, considering our "tendencies," especially 
after we have adduced examples of true "nummuline layer" in cracks 
in this rock, J we do not expect that any statement of ours will meet 
with his acceptance. We would, however, ask Dr. Dawson — why he 
discards the detailed testimony of one of his co-believers, Professor T. 
Eupert Jones, who particularly mentions that the "Irish Green," as 
" shown to the practised eye," contains every one of the features diag- 
nosed for "Eozoon Canadense"?§ Quite sufficient has been adduced 
^to prepare the reader for Dr. Dawson's refusal to accept the "chamber 
casts," and their "aciculi," in Skye ophite, as eozoonal: our figurejl is 
summarily set aside by the gratuitous statement, that it merely" shows 
granules of serpentine hispid with acicular crystals"! In our late 
paper on the Skye Ophite^ an additional figure is given, representing 
a few " nearly parallel cylindrical processes" attached to the curving 
edge or surface of a piece of serpentine (" chamber cast"), and which, 
before decalcification, " traversed the carbonate of lime," forming 
* " Proceedings of the Royal Irish Academy," vol. x.,pp. 546, 547. 
t See Postscript. 
X " Proceedings of the Eoyal Irish Academy," vol. x., pi. xlii., fig. 6 ; " Quarterly 
Journal Geological Society," vol. xxii., pi. xiv., fig. 4. 
§ " Geological Magazine," vol. ii., pp. 88, 89. 
il " Proceedings of the Koyal Irish Academy,'' vol. x., pi. xliv., fig. 10. 
% lb., New Series, vol. i., pi. xiv., fig. 5. 
