164 Dr. P.M. Dunean on Fossil Corals and Echinoderms 
6. Placotrochus deltoideus, n. sp. PI. V. fig. 5. 
The coral is conical, finely pedicellate, greatly compressed 
inferiorly, less so superiorly, has a rugged, sharp, not very pro- 
minent costal projection on either side, but is not spined. The 
calice is large, elliptical, with rather acute ends ; apparently, the 
smaller axis is higher than the longer; its wall is thin, and the 
fossa is shallow, except centrally, where it is deeper and presents 
the thin lamellar columella. The septa are numerous, unequal, 
the larger touching the columella and joining it by small pro- 
cesses, the smaller reaching but a little distance inwards. There 
are six systems and five incomplete cycles. The septa are not 
exsert, are feebly arched, and are very delicate; the lamine are 
granular, and their internal margin is often wavy. The colu- 
mella is very sharp, thin, faintly papillate, and distinct. The 
coste are small, except the lateral crests. The epitheca is 
_ strongly developed, being in arched ridges. The costz are often 
chevroned beneath it. The lateral crests form an angle of 60°. 
Height of coral 1 inch; length of calice ;=% inch, breadth of 
calice ;4, inch. 
Locality. Muddy Creek, South Australia. 
Variety: Bursarius, with the lateral crests forming convex 
ridges inferiorly. 
7. Balanophyllia Australensis, un. sp. PI. VI. fig. 1. 
The corallum is pedicillate, free, long, cylindrical, tapering 
and occasionally curved. The calice is elliptical, the fossa is 
shallow, the septa are not exsert, and the columella is large. 
There are five cycles of septa in six systems, the smaller septa 
joining others very close to the wall of the calice, which is thin. 
The coste are numerous, equal, and consist of fine laminz, each 
of which has two rows of delicate dentations connected trans- 
versely. The epitheca is seen near the base. 
Height of coral 14 inch; width of calice =45 inch. 
Locality. Muddy Creek, South Australia. 
8. Trochoseris Woodsi, n. sp. PI. VI. fig. 2. 
The coral is fixed by a small pedicel, above which it expands 
at first irregularly, and then largely. The wall is covered by a 
pellicular epitheca, which shows traces of subequal coste. The 
calice is widely open, irregularly circular, with a thin edge and 
a small central fossula. The septa are not exsert, are crowded 
and delicate, there being not much difference in the size of those 
of the principal cycles; in six systems of five cycles, with half 
a sixth in each. The smaller septa very generally join the 
larger, and the larger reach the central fossula, The lamine 
