Geology and Natural History. 65 
cof followed in the profile, fig. 1, where the upper ray, By emerges 
e lower one, and the lower ray, C, as the upper on 
s the ray A enters the pervendicnlas line above th lower 
edge, it will not be reflected out of its plane, while the rays B 
as A emerge at the corresponding opposite point, 
a perspective representation of the prism. — Journal 
Franklin. Institute. 
Il. GroLtogy anp Natrurat History. 
1. On the Eozoon ; by Dr. Dawsoy.—Dr. Dawson published a 
reply to the first of the extended memoirs of Messrs. King and 
is said by the ae ere describer of the Eozoo 
In opposition to these facts, and to the careful deductions drawn 
from them, the authors of the paper under consideration maintain 
that mae str uctures are mineral ahd orystarane I believe that in 
t 
2 “plastic-force” as a mode of scedun tin for fossils would not be 
tolerated for am ment, were it not for the great antiquity and 
highly crystalline aatdinion of the rocks in which the structures are 
found, which naturall create a prejudice against the idea of their 
being’ fossiliferous, That the authors themselves feel this is appar- 
ent from the s slight manner in which they state the leading facts 
above given, and from their evident anxiety to restrict the question 
to the mode of occurrence of serpentine in limestone, and to ignore 
= Laveounens of Kozoon preserved under different mineral condi- 
Wi th perence to the general form of ers and its structure on 
the larg e scale, I would call attention to two admissions of the 
authors of the paper, w oa appear to me to be fatal to their case: 
First, they admit, at page 533 [ henner % vol, x], their “inabil- 
ity to andthe pairs ily” the alternating rol tbe gee carbonate of 
Roz inerals in the typical s specim of Canadia 
beg They oak a feeble attempt to establish an poneny 
between this and certain concentric concretionary layers; but the 
e 
Z0On pres 
any concretionary hypothesis. If, however, they are unable t 
ion the lamellar’ structure alone, as it appeared to Logan in a 
°9, is it not gar to attempt to explain it away now, when 
yttain minute internal structures, co: ing to what might 
ay been exp : rigin, are 
ted on the hypothesis of its organic origin, 
ded to it? If I affirm that . certain mass is the trunk of a fossil 
AM, 
Jour. Sot.—Turep Series, Vor. 1V, No. 19.—Jury, 1872, 
5 
