123 
are not sufficiently cliaracteristic to decide the point. The base, composed 
of thin pieces united into a widely expanded cup, has a diameter of four 
millimetres only, and is nearly one millimetre high. 
Horizon and Localities. — The fragments in question were found, some 
in a yellowish- grey sandstone at Glen William, others in a grey argil- 
laceous limestone between the Hunter and E^ouchel Hivers, and at Burra- 
good, on the Paterson. 
TBIBRACHYOCKINUS, McCoy. 
Tuibrachyocrinus Clarkei, Me Coy. ^ 
PI. VI, Pig. 5. 
Tribrachyoermus Clarlcei, McCoy, 1847, Ann. Mag. Nat. Hist., XX (1), p. 228, pi. 12, fig. 2. 
The calyx of the type specimen of this the only species yet known of this 
somewhat anomalous genus can acquire considerable proportions, and attain a 
diameter of from five to six centimetres. A nearly perfect specimen of average 
size will serve to give an exact description of it, which will he rendered clear by 
a horizontal projection of its various pieces. The base is composed of three 
hasals, of which two are larger than the third, and pentagonal in form, the 
small one being tetragonal. The arrangement of these pieces is exactly that 
of the hasals of Flatycrinus. This base is slightly raised, so as to form a very 
wide cup with a pentagonal rim. To each of the five edges is joined a 
sub-radial, three of which are also pentagonal, while the other two, adjacent 
HR. Etheridge, Junr., 0^5. cit., pp. 80-94, pi. 13, figs. 2-4, pi. 14, fig. 3, pi. 15, figs. 6-8 ? 5, pi. 17, 
figs. 2-4.— W.S.D.] 
S 
