117 
Column. 
PL XVIII, Fig. 4. 
Ohs. — 'Portion of a smaller column, also witli a nodal-joint, which has a 
rounded periphery, and is larger and projects beyond the internodal- joints. 
Every fourth joint amongst the latter is, as in PI. XVII, Pig. 5, larger than 
the others, and slightly rounded, the internodal being flat. 
Locality and Horizon . — Ellalong, Mt. Vincent, Co. Northumberland 
( C. Cullen) ; — Muree Kock, Upper Marine Series. 
Radial Plate. 
PL XX, Fig. 9. 
Ohs. — An impression of a thick radial with a large, clearly marked 
articular margin, and hearing diverging lines of coarse granules or small 
tubercles, and a medium line extending down the centre of the plate. 
Probably Trihrachiocrinus. 
Locality and Horizon . — Mt. Terry, Jamheroo, Co. Camden {B. O^ 
Enyelhardt, Collection Australian Aluscum) : — Upper Marine Series. 
ENLARGED STEMS. 
Ohs . — Crinoid stems in tlie Carboniferous of other countries are fre- 
quently found enlarged and of irregular growth., arising from the action of 
parasitic organisms within and without the stems. A full description of these 
will he found in the paper quoted below. ^ Irregularities of this nature are 
usually accompanied by a depression of the stem surface, or a hole, leading to 
the interior of the latter. Instances of this nature are correspondingly rare 
in our Permo-Carboniferous, one only having come under notice. (PI. XVIII, 
Pig. 3.) 
It was shown by the late Mr. J. Ilofe^ that one form of enlargement 
was caused by the work of a parisitic coral, Moniloporacrassa, M‘Coy, sp., and 
other methods of distortion have been described by the "Writer, through the 
' R. Etheridge, jun. Observations on the Swollen Condition of Carboniferous Crinoid Stems. Proc. Nat. 
Hist. Soc. Olasyow, 1879. 
^ Note on the Cause and Nature of the Enlargement of some Crinoidal Columns. Geol. Mar/., 1869, VI, 
p. .351. 
