GEODITES. 151 
which I regard as belonging to the same species. These spicules range from 2°5 
mm. to 13 mm. in length, and from -2 to 1 mm. in thickness. 
At the time of writing the ‘Cat. Fos. Sponges,’ I had only seen two of the 
bifid zone-spicules, which I then thought might be distinct from Geodia ? antiqua ; 
the specimens which I have since received from Mr. John Smith confirm this 
opinion. The relatively large proportions and the general characters of these 
spicules readily distinguish them from any others of this sub-order, whether fossil 
or recent. The spicules are siliceous, and in the same condition of preservation as 
those of Hyalostelia with which they occur. 
Distribution.—Carboniferous : Upper part of Lower Limestone series, Law 
Quarry, Dalry, Ayrshire (J. Smith, J. Bennie). 
32. Gropites HastaTUs, Hinde, sp. nov. Plate IX, figs. 11, lla, b. 
The distinctive zone-spicule of this species has a straight, gradually tapering 
shaft, and simple head-rays directed obliquely forwards at an angle of between 25° 
and 30° with the shaft. Associated in the same bed with the trifid spicules are 
numerous, more or less curved, acerate spicules, from 1°2 to 2 mm. in length, and 
from ‘07 to ‘15 mm. in thickness, which may be regarded as belonging to the same 
species. The head-rays of the trifid spicule are conical and pointed; they are *25 
mm. in length and nearly *1 mm. wide at the base. 
The disposition of the rays of the trifid spicule readily distinguish it from those 
of G. antiquus; it is also smaller, and the acerate spicules are likewise smaller 
than in the allied form. 
These spicules are now of chalcedonic silica; they occur in thin layers of cal- 
careous shale between massive beds of limestone. By dissolving the shale in acid 
they are obtained free from the matrix. 
Distribution.—Carboniferous Limestone: Clitheroe, Lancashire. 
33. GuEODITES corNUTUS, Hinde, sp. nov. Plate IX, figs. 12, 12 a—12 e. 
The zone-spicule in this species has a straight, slender, gradually tapering 
shaft and simple head-rays, which spring nearly at right angles from the top of 
the shaft and curve backwards. This zone-spicule is accompanied by straight or 
slightly-curved, fusiform, acerate spicules from ‘8 to 13 mm. in length, and from 
‘05 to ‘07 mm. in thickness. In an adjoining locality a slender anchor-spicule 
