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, Dairy, Ayrshire (J. Smith, J. Bennie). 



32. GIeodites hastatus, Hinde, sp. nov. Plate IX, figs. 11, 11 a, 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 0. 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. G-eodites coenutus, 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 1*3 mm. in length, and from 

 •05 to "07 mm. in thickness. In an adjoining locality a slender anchor-spicule 



