392 Dr. F. A. Bather on British Fossil Crinoids : 
In pentagonal forms therefore the cracks coincide with the 
angles. This indicates that the weak stereom occupies the 
ligamentar tracts, as might be expected. Further evidence 
of this is afforded by the five interradial pillars of dark 
colour that run through every internode from top to bottom 
and are seen on broken or ground surfaces (e. g., E 22024), 
for the colour is due to the carbonized remains of the 
ligaments (see-Bather, 1893, ‘Crin. Gotland,’ p. 151, and 
1909, ‘Trias. Echin. Bakony,’ p. 204). 
In mean Diameter the fragments vary from 4 mm. 
(E 21953) to 9:4 (E 22027). This doubtless represents 
growth, and the larger forms are by far the more common 
in the collection. 
The Side-Faces in a large number of specimens are quite 
smooth, but in some there are small granules scattered over 
the surface (E 21966) ; these granules may be elongate 
either vertically or transversely, and may run together to 
form irregular lines, a sort of vermiculation (E 21965) ; or 
they may run into transverse ridges, at the equator and the 
sutural margins (EH 22024); the commonest arrangement 
seems to be one ridge at the equator of the columnal, either 
compound (E 21968) or simple (E 21969, cf. d’Archiac’s 
fig. 17 a), and this is often accompanied by an equatorial 
swelling of the columnal (E 22022). In such cases the 
intervening granules, if any, tend to lie beside each radius 
(E 22020 and E 22023). 
This leads to another series of variations, namely from a 
plane side-face, producing a straight-sided column (E 22021), 
through slightly swollen, to obtusely ridged (E 21970 to 
E 21974). ‘The ridge is often sharply cut and may be 
smooth, or accentuated by the line of granules previously 
mentioned. In one specimen, E 21985, the side-faces are 
slightly excavate, or, in other words, the columnal is thickened 
at the sutures. 
In the smooth specimens the columnals are equal in 
height (cf. d’Archiac’s fig. 18), except for the slightly higher 
epizygal and slightly lower hypozygal. The following are a 
few measurements :— 
E 22020. E 22021. LE. 21959. 
mm. mm. mm. 
Mean diameter ...... Fish 84 8-5 
Height BY Deas «SE re ee 21 2-4 2-8 
Inequality in height of columnals usually becomes manifest 
