Examination of " Eozoon." 281 



muline wall ;" yet lie inconsistently asserts, " If tlie chambers 

 and tubuli of a nummulite were infiltrated with serpentine, 

 and the calcareous skeleton were removed by acid, the appear- 

 ance presented would be exactly that figured" in one of our 

 delineations of it. 



Referring to his original description of " Eozoon y'' we find 

 it stated that " in decalcified specimens, the free margins of 

 the casts of the chambers are often seen to be bordered with a 

 delicate white glistening fringe ; and when this fringe is ex- 

 amined with a sufficient magnifying-power, it is seen to be 

 made up of a multitude of extremely delicate acicuUy stand- 

 ing side by side like the fibres of asbestos:" and reference 

 is made to fig 4, pi. ix., accompanying the memoir. Dr. Car- 

 penter asserts that '' Professors King and Rowney certainly 

 have not seen " any thing answering to this description, " if 

 they can identify it with a film of chrysotile or asbestiform 

 serpentine, and can assert that in its typical condition it occurs 

 in cracks or fissures of the serpentine." As the figures which 

 represent the fact that sustain this identification (somewhat 

 incorrectly expressed by Dr. Carpenter) are contained in a 

 publication less known, considering its merits, than it ought 

 to be, we have selected two additional examples, detected in 

 a mounted section, kindly presented to one of us by himself 

 some years since, of " Eozoon^'' in its laminated condition, 

 from a specimen of Canadian ophite*. In the examples 

 represented in fig. 3 " extremely delicate aciculaj " (h) are 

 seen " standing side by side," exactly as in Dr. Carpenter's 

 illustration ; while in the other, given under fig, 4, similar 

 aciculffi occm-, but more obviously separated The latter 

 may be taken for typical examples of the " nummuline wall" 

 — the " calcareous lamella perforated by minute tubuli " (they 

 show the calcareous separations removed by decalcification, 

 the casts of the tubuli alone remaining). But now comes the 

 point which is to decide whether we are labouring under 

 " confusion in the mind," or Dr. Carpenter is " suffering under 

 tubulation on the brain." Reverting to the example repre- 

 sented in fig. 3, the acicula3 are seen to " stand side by side " 

 (when, of course, the interspaces must be much thinner than 

 they are in example fig. 4), and to be closely compacted, 

 with absolutely nothing more separating them than their own 

 divisional lines ; and as such they pass here and there into the 

 condition of true chrysotile {c) , which actually nms into, and 

 forms a vein in, the adjacent serpentine (a), retaining the green 

 colour of the structui-eless mineral. The change from one 



• Tho entire section is represented in ' Proceedings Roval Irish Acad.' 

 vol. X. pi. xli. fig. 4. 



