CORYNELLA ELEGANS. 221 
pore-like openings between the fibres. When the surface is weathered it becomes 
rough, and occasionally is channelled by open furrows. These ostia and pores 
are present on the stem as well as on the body of the sponge. The cloacal tube 
extends down to the stem; its wall is well marked, and perforated at definite 
intervals by the apertures of the excurrent canals, which are about °35 mm. in 
width. 
The skeleton consists of a fairly close reticulation of narrow fibres from 
‘06 mm. to ‘18 mm. in thickness, consisting of subequal three-rayed spicules 
interlaced together (Pl. XV, figs. 3d, 3e). The rays of these are about ‘16 mm. 
in length. In addition to these, delicate tuning-fork spicules can occasionally be 
seen in the sections, which appear to be arranged nearly parallel with each other 
on the outer portion of the fibres (Pl. XV, figs. 3 f, 3g). In the lower portion of 
one of the sponges there were bundles of these spicules filling the spaces between 
the ordinary fibres. One of these forms measured ‘17 mm. in length. Within the 
same sponge there were also several sagittate four-rayed spicules (Pl. XV, fig. 3 h) 
quite distinct from those forming the fibres, and it is possible that these may 
belong to the wall of the cloacal tube. The only dermal layer in these sponges is 
a small band round the lower part of the stem. 
These sponges are not uncommon in the Bradford Clay and the Cornbrash, 
and they retain their spicular structure in a very perfect condition. 
Distribution.—Bradford Clay at Bradford-on-Avon, Wiltshire, and from the 
Box Tunnel, Bath. Cornbrash at Langton Herring, near Weymouth. Also from 
the ‘‘ Calcaire a Polypiers”’ at Ranville and Benouville, near Caen, France. All 
the specimens figured are from the Walton Collection in the Woodwardian 
Museum, Cambridge. 
29. CoryNELLA ELEGANS, Hinde, sp. nov. Plate XV, figs. 4—4b. 
Sponges simple or compound: the simple forms are round or ovate with a 
short stem ; the compound forms consist of three or four small rounded individuals, 
sessile on a common base, and usually partially amalgamated with each other. 
Small simple forms are not more than 6 mm. in height by 5 mm. in diameter, 
whilst the compound specimens are about 14 mm. in breadth by 7 mm. in height. 
The surface has small subcircular ostia, ‘3 mm. in width, and small irregular 
apertures between the fibres as well; the summits are rounded, the oscule is 
2mm. in width, its rim does not project above the general surface ; the cloacal 
tube is perforated by elongate canal apertures. The excurrent canals are about 
‘4mm. in width. The fibre forms a somewhat open mesh; it varies from ‘07 mm. 
FF 
