202 J. W. Dawson—Mibius on Eozoon Canadense. 
added, though perhaps not as an argument, that the discovery 
of Hozoon affords a rational mode of explaining the immense 
development of limestones in the Laurentian age; and on the 
other hand that the various attempts which have been made to 
tural; but so far as these have been attempted they have con- 
sisted merely in the effort to eliminate the accidental conditions 
of fossilized bodies, and to present the organism in its original 
pon. Such restorations are not to be taken as evidence, 
ut only as illustrations to enable the facts to be more easily 
understood. It is to be observed, however, that in the study 
of such fossils as Hozoon, the observer must expect that only a 
small proportion of his specimens will show the structures with 
any approach to perfection, and that comparison of many speci- 
mens prepared in different ways may be necessary in order to 
understand any particular feature. A single figure or a short 
description may thus represent the results of days spent in the 
field in collecting, of careful examination and selection of the 
specimens, of the cutting of many slices in different directions, 
and of much study of these with different powers and modes 0 
illumination. My own collection contains hundreds of pre- 
parations of Kozoon, each of which represents perhaps hours 
of labor and study, and each of which throws some light more 
or less important on some feature of structure. The results of 
labor of this kind are unfortunately very liable to be regarded 
as subjective rather than objective by those who arrive at con- 
clusions in easier ways. 
Taken with the above cautions and explanations, the memoir 
of Professor Mébius may be regarded as an interesting and 
useful illustration of the structures of Eozoon, though from 
a point of view somewhat too limited to be wholly sat 
istactory. 
