Pia 
te i 
_ determine the systematic position of the genus. For a 
254 FOSSILS FROM THE PALHOZOIC ROCKS OF N.S.W. 
considered, although perhaps simple mineralization may account 
for it.! It will be seen from the following notes on the i 
Tentaculites that the latter of these suppositions is probably the 
correct one. 
The late Mr. J. W. Salter also touched upon this subject ina 
paper on Cornudites and Tentaculites, read before the British Associa- 
tion in 1845. He described a laminar structure as existing at the 
thickened nodes or annulations of the shell, the texture being 
looser here than in other parts of the latter, thus showing & 
transition towards the structure of the genus Cornulites.’ 
The sections of the limestone forwarded by Prof. Liversidge, 
scattered 
from the random manner in which the Zentaculites are 
more crowded together in the annulations or circular coste of the 
shell. These tubuli, so far as I have examined them, do not 
are seen to be densely crowded with these tubuli, which are 
necessarily all of the same length, and in each annulation they 
appear to tend from the upper and lower margins towards 
centre. When any fragment of the shell contained m the — 
mass of the limestone is sectioned parallel to the longer 2x18 © 
tubes are seen as small crowded black dots. Pl—Fig. 10a 
The internal and external walls of the shells, or yee 4 
Tentaculites, correspond with one another, the inner following ' 
outline of the exterior, as will be seen by a glance at the enlal 
figure of a portion of one side of a tube. 
In one or two examples there does appear 
to be a division oF 
the shelly matter into lamine, which would give colour to ¥! 
- Richter’s observations on the presence of the columnar i pid 
-but as it certainly is not present in all, I to ay aS 
do not wish 
much stress on the point. 
years 
1 Zeit. Deuts. Geol. Gesellschaft, 1854, vi, p. 279. 
? Brit. Assoc. Report for 1845, pt. 2, p. 57. 
