9i 
name pending the discovery of more perfect specimens. Especially is this the 
case in the light of PL XVII, Pig. 2-4, wherein is exemplified the difference 
in outline produced hy distortion due to pressure. 
Locality^ and Horizon. — Near the lleservoir. West Maitland {II. D. 
Walsh) \ and hack of the College, Camphell’s Hill, West Maitland, Co. 
Northumherland ( W. D. Fihner and J. 3Iitchell) ; Singleton, Co. Northumher- 
land (-S'. Dodds) ; Ilailway Cutting at AVollongong, Co. Camden ( C. Banks 
of the Minumurra Biver, near Jamheroo, Co. Camden {B. G. Enyelhardt ) : — ■ 
Upper Marine Series. Nowra, Co. St. Vincent ( (7. G alien) \ — Nowra Grit% Upper- 
Marine Series. 
It will he seen from this that Trihrachiocrinus Clarkei, M‘Coy, has not 
been met with out of the Uirper Marine Series. 
Tribrachiocrinus ornatus, sp. non. 
PI. XIX. 
Sp. Char. — Calyx large, cup-shaped, hut asymmetrical, produced 
towards the posterior side ; greatest periphery along the basi-radial sutures. 
Base flattened, gently concave inwards to the columnar facet. Ornament of 
the test very characteristic ; each basal plate hears a central boss, from which 
four ridges radiate to the hasi-radial sutures ; the arm-carrying radial 
plates each hear two diverging ridges from a central point on the costo- 
articular margin to tliose points on the hasi-radial sutures cut by the ridges 
of the basal plates, where the union of the two sets again produces prominent 
bosses. 
Ohs. — I regard the subject of PI. XIX as specifically distinct from 
Trihrachiocrinus Clarkei, on account of the ornamented condition of the 
radial and basal plates. Tlie condition of the fossil, a cast in the Nowra 
Grit, a matrix by no means lending itself well to the preservation of organic 
remains, does not permit of a more definite or extensive specific diagnosis than 
the aliove. As I have laid considerable stress on the non-appearance of 
sculpture externally on the plates of T. Clarkei, some explanation of the 
adoption of this character as a specific feature is necessary. 
’ By M‘Coy T. Clarkei was recoi’ded from Darlington, in soft grey shale {Ann. Mag. Nat. Hist., 1847, XX, 
p. 229) ; and by De Koninck, from the Muree Quarries, Raymond Terrace. (Foss. Pal. Notiv.-Oallcs ditSud, Pt. 
ii, 1877, p. 163. 
^ The erpiiv.alent horizon in the Illawarra Coal-field, of the Muree Rock in the Hunter River Co.al-field, 
from which T .Clarkei was recorded by Prof. L. G. de Koninck. 
