superiorly, equal, stout throughout, but of diminished thickness 

 towards their central terminations. For some distance down they 

 are free, and enclose a deep, longitudinal fossa, but a little below 

 the upper boundary of the wall they unite by stout processes to 

 form a parietal columella. 



Height of corallum, 5-5 mm.; length of calice, 3-5 mm.; 

 breadth of calice, 2 mm. 



Locality^ <fec. — In the Eocene strata at Muddy Creek, Victoria- 

 Collected by Professor Tate. A single specimen (the type) has 

 been in my cabinet for several years, but I hesitated to describe 

 it until others came to hand. Just lately Mr. T. S. Hall showed 

 me three rolled examples of the species which he had collected at 

 Forsyths, on the Grange Burn, one of the sections included under 

 the general term " Muddy Creek beds." Great care has to be 

 exercised in collecting at Forsyths, as owing to the junction of 

 the Miocene and Eocene there, the lower part of the section 

 contains some derived Eocene fossils mixed with the prevailing 

 Miocene ones. The type specimen, which is well preserved, came 

 from an undoubted Eocene exposure just below Clifton Bank, and 

 there is, I think, little doubt that the worn specimens collected 

 by Mr. Hall are traceable to the Eocene. A very minute and 

 young example of either this or a closely allied species was 

 obtained by the same gentleman from the " Ledge " at Spring 

 Creek.* 



The next coral I place in Ehrenberg's genus Desmophyllum, 

 but instead of six systems of septa, as in the type species D. crista- 

 ^alli, it has eight. The number of cycles is besides not constant 

 in the systems. Several writers have, however, drawn attention 

 to the variability of the species of this genus in certain characters. 

 Thus Ten.-Woods named a recent species from Fiji D. quinariunif 

 in allusion to the five systems of septa present.! 



Again, one of the earliest described species D. Taurinense 

 Edw. and H., from the Falunien of Turin, has, according to De 

 Fromentel, also five systems of septa. 1 In his detailed description 

 of the same species, Michelin states that it is remarkable for ten 

 stout septa (dix grosses lamelles), each of which is also accom- 

 panied by two very small ones.§ The base is also attenuated 

 and not broad, as in the type of the genus. The full details and 



* Since writing the above an example of this coral has been sent to me 

 by Dr. Verco, who dredged it in Backstairs Passage at a depth of 22 

 fathoms. Holcotrochus scriptus is therefore recent as well as fossil. It is 

 accompanied in the latter locality by another species of the same genus, 

 which will be described shortly. 



+ 0n a New Species of Desomophyllum. Linn. Soc, N.S.W., 1878. 



J Introduction a I'etude des Polypiers fossiles 1858-61. 



§Icon. Zooph., p. 39. 



