30 
OrnitHorus Graciuis. The former is so called from 
the resemblance to the domestic fowl: for convenience 
sake, in this and other instances, we use the whole for 
apart. It is about three inches in length, and the 
Ornithopus Gracilis about two. 
This latter specimen is particularly interesting. It 
consists of two parts, which open like the covers of a 
book. 'These covers present four impressions: first, 
the superficial, which is distinct, slender, and beauti- 
ful — the heel is broad; second, corresponding with 
this depression and on the inside, is a figure in relief 
as distinct as the depression; third, on the inside of 
the second cover is a depression corresponding with 
the relief last mentioned; fourth, on the outer side is 
a second relief corresponding with the second depres- 
sion, but less distinct than either of the other three, 
still, however, exhibiting three toes pointing ante- 
riorly, but the hind toe is wanting. ‘The whole of this 
double slab forms a series of cameos and intaglios, 
measuring four inches by three, and in thickness an 
inch and a quarter. 
GROUP FOURTH. 
Of the fourth group we have five specimens. ‘The 
Trienopus, so called from its resemblance to a trident, 
