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RECORDS OF THE AUSTRALIAN MUSEUM. 
tubes existed in the hard parts of Sponges, Foraminifera, Corals, 
Brachiopoda, and Univalve and Bivalve Shells, and contained 
sporangia ; he regarded them as unicellular fungi. The late Prof. 
H. N. Moseley appears also to have worked at similar endo- 
phytes in 1875, but I regret a want of knowledge of his 
reference. 
The last paper to which I shall refer is Duncan’s second com- 
munication — “On bodies penetrating Decent and Tertiary Corals,” 
wherein he terms the form Achly a penetrans * He remarks that 
a parasite closely resembling this lived in the tissues of Upper 
Silurian Corals and Foraminifera, “the main differences between 
the ancient and modern forms consist in the larger calibre of some 
of the filaments of the first, their long, often unbranching course, 
and the frequent development of Conidia- looking bodies within 
them, and the spherical shape of the spores.” It does not appear 
to be quite clear whether Duncan here retains the name he else- 
where proposed for the “ ancient ” form, viz., Palceachyla per fora ns, 
or includes both the “ancient and modern forms” under Achlya 
penetrans. 
I am quite in accord with an observation of Mr. A. C. Seward, f 
who says : — “ 1 1 is generally a very difficult, and often an impossible 
task, to discriminate between the borings of fungi and algae in 
fossil material.” In this belief I shall simply leave the tubes 
described by me as Pahmchlya tortuosa in the position formerly 
assigned to them, pending further investigations that future dis- 
coveries may afford. 
The very much more intricate growth of the tubes described in 
preceding pages, and their smaller calibre, induce me to consider 
them as distinct from P. tortuosa of the Pernio Carboniferous, and 
for the sake of clearness they may be known as P. torquis .* 
In considering the systematic position of the moniliform chains 
of cells, many difficulties present themselves, and in a preliminary 
investigation of this kind — and it can only be considered prelim- 
inary — I merely wish to point out the very strong general re- 
semblance these chains of cells bear to certain unicellular algae of 
the group Schizophycem, and particularly the Nosfcocaceae. The 
moniliform chains are very like the trichomes of Nostoc , allowing 
for the absence in the former of irregular interlacing, and the en- 
larged black cells equally resemble the heterocysts of the same 
genus, which seem to be — so far as my sections enable me to 
judge — either basal, terminal, or intercalary. Compare the many 
excellent figures given by Mr. M. C. Cooke, particularly those of 
* Proc. Roy. Soc., xxv , 1876, 174, p. 262. 
t Seward — Fossil Plants, i., 1898, p. 129. 
j i.e.. That which is twisted. 
