2 



BRITISH FOSSILS. 



like projection, deeply indenting the cavity of the mouth. Of how many 

 separate ossicles each of the buccal processes was composed the spe- 

 cimen affords but very indistinct indication. They seem to affect a 

 slightly falcate form at their extremities. The arms were composed of 

 alternating somewhat quadrate ossicula, the sides of which were deeply 

 indented superiorly, in order to form spiniferous crests. The spines 

 were apparently short, and not equal in length to the length of an 

 ossicle, obtuse, and few in a row. The under surfaces of the brachial 

 ossicula were not indented laterally. The central portions of the upper 

 surfaces of the brachial ossicles were hollowed out slightly, and the 

 sutures between them deeply impressed. About twelve of the brachial 

 ossicles were imbedded in the disk, and the parts of the dorsal surface 

 of the latter, corresponding to the arms and central skeleton, do not 

 present traces of scales, a feature seen in existing Euryales. 



The dimensions of Professor Sedgwick's specimens are as follows : — 



Breadth of disk, Of^ths inch. 



Average breadth between the arms, Ofj^^s inch. 



Breadth of an arm, at its junction with the body, O^^th inch. 



Locality and Geological Horizon. — Silurian, from Ludlow rocks at 

 Docker Park, near Kendal, Westmoreland (specimen figured), asso- 

 ciated with Encrinites, and at Benson Knot, also near Kendal, in hard 

 sandstones, full of characteristic Ludlow fossils. Collected by the Rev. 

 Professor Sedgwick and Mr. John Ruthven. 



Explanation of the Plate. 



Fig. 1, under, and Fig. 2, upper side of the Docker Park specimen. Fig. 3. Restora- 

 tion to show the probable form and appearance of the animal. Fig. 4. Diagram of base 

 of an arm, buccal processes, and position of ovarian openings. 



Edward Forbes. 



April, 1849. 



