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imperfectly preserved, and that in such cases the casts of the tubuli 
may appear to he glued together hy concretions of mineral matter, or 
to be broken or imperfect. But this occurs in all fossils, and is 
familiar to any microscopist examining them. How difficult is it in 
many cases to detect the minute structure of Nummulites and other 
fossil Foraminifera. How often does a specimen of fossil wood 
present in one part distorted and confused fibres or mere crystals, 
with the remains of the wood forming phragmata between them, when 
in other parts it may show the most minute structures in perfect 
preservation. But who would use the disintegrated portions to 
invalidate the evidence of the parts better preserved ? Yet this is 
precisely the argument of Professors King and Bowney, and which 
they have not hesitated in using in the case of a fossil so old as 
Eozoon, and so often compressed, crushed, and partly destroyed hy 
mineralization. I have in the above remarks confined myself to what 
1 regard as absolutely essential hy way of explanation and defence 
of the organic nature of Eozoon. It would be unprofitable to enter 
into the multitude of subordinate points raised by the authors, and 
their theory of mineral pseudomorphism as discussed by my friend 
Dr. Hunt ; hut I must say here that this theory ought, in my opinion, 
to afford to any chemist a strong presumption against the validity of 
their objections, especially since it confessedly does not account for all 
the facts, while requiring a most complicated series of unproved and 
improbable suppositions. The last point which I shall mention is the 
taunt that so little further progress has been made in the investigation 
of Eozoon. With reference to this, I beg leave to doubt whether a 
process of confounding the actual structure of Eozoon with all manner 
of dendritic and crystalline forms, in the way followed hy the authors, 
would constitute progress. But in so far as careful comparison with 
all specimens which have been recently found is concerned, some 
progress has been made, and I trust that it will soon he possible to 
bring forward not merely additional specimens illustrative of the 
structure of Eozoon, hut fresh evidence of its wide geographical 
range, and also links of connection with fossils of the Pakeozoic rocks. 
The discovery recently made in Massachusetts, and alluded to hy 
Messrs. Bowney and King, is itself not without importance. In the 
meantime I am content to accept the investigations of Messrs. King 
and Bowney as nearly exhaustive of the natural history of those 
imitative forms which may he confounded with Eozoon, and therefore 
as in a certain way useful in the further prosecution of the subject. 
As already stated, I am at this moment engaged in following out, as 
opportunity offers, two lines of investigation bearing on the following 
points: — (1) The study of the Lower Silurian and Primordial suc- 
cessors of Eozoon ; and (2) that of the tubulation and other structures 
similar to those of Eozoon preserved in the Pakeozoic rocks.” 
The Histology of the Penis . — One of the best papers that we have 
for some time seen is that on the above subject, in a recent number of 
the c New York Medical Journal.’ It deals very fully with the whole 
subject, and is illustrated hy a number of cuts demonstrating the more 
important points in the histology of this organ. Besides the author’s 
