52 
important character in this species. These bones are longest 
near the oral aperture, and gradually diminish towards the end 
of the rays. They form a beaded structure of considerable 
strength, which supported a great number of small, short, 
stout spines; these appear to have passed round the sides of the 
rays and covered the dorsal surface. A few of the spines are 
seen in the twisted part, which exposes a portion of the upper 
surface. This spinous condition of the tegumentary membrane 
has suggested the specific name which I have given to this 
new Jurassic Star-fish. 
The small ossicles which occupied the central portion of the 
ambulacral areas are absent, and there remains only the vacant 
spaces they at one time filled in (see figure.) 
Affinities and Differences.—This organism differs so much 
from the other fossil species of the Genus Uraster that it may 
probably prove to be the type of a new genus when more details 
are learned anent the anatomy of the skeleton, by the discovery 
of additional materials to work upon. In the meantime I have 
grouped it with the Urasters, to which it is so closely related 
by general characters, whilst it differs in some others, as for 
- example, in the presence of the beaded ridge formed by the 
ossicles which bound and limit the ambulacral areas. 
Locality and Stratigraphical Position.—This specimen was 
obtained from one of the shaly beds of Forest Marble, near 
Road, Wilts. It appears to be rare, as I can find no record 
of any other Star-fish having ever been found in the fossiliferous 
beds of that locality. . 
The above drawing was very carefully made on wood, by the 
late eminent artist Mr. C. R. Bonz, and engraved by Mr. Luz. 
It represents the fossil enlarged two diameters, in order to 
exhibit the minute details of the anatomy of this species. 
