1866.1 GUMBEL — ON LAURENTIAN ROCKS. 93 



and they not improbably represent those stolons or connecting 

 channels with which Carpenter has made us acquainted. 



In the decalcified specimens, delicate very slender string-like 

 leaflets were very frequently observed, stretched between the 

 serpentine granules; but they presented no discernible organic 

 structure, and are perhaps only the casts of small crevices. More 

 remarkable are the numerous canals filled with carbonate of lime, 

 which traverse the serpentine granules, and at the surface of these 

 are expanded into funnel shapes. They appear to represent cross 

 connections between the calcareous skeleton. 



As my object at present is merely to shew the presence, in the 

 primitive limestones of Bavaria, of forms corresponding to the 

 Canadian Eozoon, I will not dwell longer on these various 

 appearances met-with in the microscopical examinations, nor on 

 the peculiar cellular structures observed in the carbonate of lime. 

 I will, for the same reason, only mention a specimen which exhibits, 

 by the side of a curved main tube, a number of secondary tubuli, 

 and farther on a parallel layer of fibres; and also another radiated 

 form which resembles a section of a Bryozoon. It is sufficient to 

 draw attention to the fact that, in addition to Eozoon, there are 

 other organic remains in these crystalline limestones. There 

 remains however to be noticed a phenomenon of some importance. 



When the lime is removed by nitric or acetic acid from the 

 interstices of the serpentine granules, there may be observed, on 

 gently moving the liquid, extremely delicate membranes, that 

 separate themselves from the serpentine grains, (which they 

 covered thickly, as with a fine white down,) and now remain 

 swimming in the liquid, so that they can readily be separated, 

 by decantation, from a multitude of heavier particles, which, 

 having also detached themselves from the serpentine mass, accu- 

 mulate at the bottom of the vessel. - These consist in great part of 

 indistinct mineral fragments, and of small crystalline needles, 

 together with distinct cylindrical portions, which are the broken 

 tubuli of the Eozoon. Besides these are, here and there, distinctly 

 knotted stems or tubules, (PL I., figs. 5, a and &,) which I dare 

 not suppose to belong to Eozoon. Various other fragments of 

 tubuli are also associated with these. 



The delicate flakes, which can be obtained by evaporating the 

 liquid in which they are suspended, shew, under a magnifying 

 power of 400 diameters, a membranous character, and peculiar 

 structures, which seem to be undoubtedly of organic origin. 



