Tertiary. | PALHONTOLOGY OF VICTORIA. [ Echinodermata. 
Prater LIX. 
CLYPEASTER GIPPSLANDICUS (McCoy). 
{Genus CLYPEASTER (Lam. restricted). (Sub-kingd. Radiata. Class Echinodermata. 
Order Echinida. Fam. Clypeasteride.) 
Gen. Char.—Testa of single walls ; subpentagonal, depressed ; ambulacra petalloid ; actinal, 
or lower, surface flat, with the mouth depressed in a narrow circumscribed hollow ; well-developed 
straight ambulacral grooves extend from mouth. ‘Tubercles small, perforated and crenulated. 
Supports between upper and lower walls formed of very numerous, needle-like (in size and shape) 
calcareous styles and fewer, thicker, irregular pillars. A row of pores in the sutures connecting 
the long sides of the two rows of ambulacral plates beyond the petals in some species. | 
Drscrrprion.—Subpentagonal, longer than broad, greatest width opposite end 
of anterior pair of petals of ambulacra; outline at interambulacral edges slightly 
concave ; lower, or actinal, surface flat, with a small central depression for mouth; 
marginal edge obtusely rounded ; surface above rather flat from edge to distal ends 
of ambulacral petals, from whence the back rises with a rather sudden moderate 
convexity to abactinal apex. The sulcated poriferous part of petals and the median 
ambulacral spaces nearly equal, the latter more prominent but less convex than the 
interambulacra; twenty-five to twenty-six pairs of pores in each half ambulacral 
petal. Genital openings small, close to the madreporiform plate. 'Tubercles nearly 
equal on upper and under surfaces, close set, with usually one or two rows of inter- 
vening miliary granules; anal opening its own diameter within the lower edge. 
Length of average specimen, 34 inches; in proportion to length (taken as 100), width, 
tov; height, ~3,; length of two hinder ambulacral petals measured from genital 
pore, +475; anterior lateral pair of petals, 33°, ; anterior odd petal, ,35,; diameter of 
anus, +o; diameter of madreporiform apex from one genital pore to opposite, +35 3 
greatest width of petals, 9,; width of ambulacral space between the rows of pores, 
yor (anterior lateral pair slightly less). Seven tubercles in a space of 2 lines on 
middle of side of upper surface, four in same space on lower surface. 
This fossil has been referred to by Prof. Duncan, the Rev. J. 
Tenison Woods, and other authorities as identical with the recent 
Eichinanthus testudinarius (Gray), found commonly on the warmer 
N. E. coasts of New South Wales and Queensland, though not on 
our cooler southern shores. The under surface of the fossil is, 
however, much flatter, and the depression for the mouth much smaller 
and more abruptly defined or suddenly bent inwards. The tubercles 
on the upper surface are also more numerous, and the granular 
spaces between them narrower, and with fewer miliary granules 
between them than in the living species, in which also the tubercles 
are smaller and with much more numerous granules between them 
than on the under side, departing widely from the fossil, in which 
DEC. VI. [ 33 ] E 
