110 REPORT—1868. 
Montlivaltia ...... { pphouemie 
ecosmilia. 
(gemmation from the wall......... Elysastrava ......... Cyathocenia. 
| Phymastrea (a)... Astroccenia. 
| Solenastrxa (6) ... Thamnastraa. 
Heliastreea (c) ...... Tsastraea. 
Thecosmilia with + oe 
straea. 
Metastreea. 
calicular gemmation ............... Lepidophyllia. 
WPREVIAl CALICES: (one -cecncs > cece eceme ch Latimeandrea. 
\ fissiparous development............ Septastreea. 
a. An evident reversion to H/ysastr@a in a recent genus. 
b. Solenastrea is a case of reversion to an ancestral Thecosmilio-Elysastrea type in the 
later Neozoic ages. 
ce. Has great probability of being a case of atavism with much modification of Theco- 
smilia and Solenastrea. 
The Montlivaltie of the zone of Ammonites angulatus are remarkable for 
their septal regularity, the amount of dissepimental endotheca, the usually 
rudimentary condition of the true wall, and the development of the strong and 
compensating endotheca. These characteristics are observed in the St.-Cassian 
Montlivaltic, and in those which are found in the strata intervening between 
the Ammonites-angulatus and the St.-Cassian beds. These structural pecu- 
liarities, in a genus whose later Jurassic species haye a perfect hexameral 
arrangement, a perfect wall, and moderate endotheca and epitheca, indicate 
the descent of the Montlivaltie from a Paleozoic stock. In Montlivaltia 
Murchisoni, Duncan, the wall and epitheca are united perfectly into one 
structure with the intercostal spaces, just as the septa of some simple Paleozoic 
corals are continuous, not with cost, but with the intercostal spaces or 
their analogues. 
M. parasitica is remarkable for its septal number; and M. simplex has 
distant and curved septa. 
M. papillata, Duncan, M. Hibernie, Duncan, and M. Haimei, Chap. et 
Dew., are closely allied species; they are broad-based, pedunculate, short, 
and turbinate, and vary greatly. The last-named species ranges probably 
over the whole area of the zone of Ammonites angulatus. 
Closely allied to Montlivaltia and Thecosmilia is the new genus Oppeli- 
smilia. Its Paleozoic aspect is distinct, the multiseptal and non-cyclical 
calice, the calicular budding, and the strong epitheca all refer it to bygone 
types. 
, These corals, from the Lias beneath the zone where Gryphea incurva and 
Ammonites Bucklandi are abundant, indicate that, like the succeeding forma- 
tions of the Chalk and the Oolite, the Lias was very coralliferous. Nothing 
marks the progress of paleontology more strongly than the ability of making 
this statement from well-ascertained data; for within a very few years the 
lias was considered so muddy a deposit as to be obnoxious to coral life, 
Now, with a great fauna, part of it indicating reef conditions and the rest 
moderately deep water, the Lower Lias will assume as great an importance 
to the zoophytologist as the Eocene. The Liassic coral-fauna reflects the 
Paleozoic as the Eocene foreshadows the Recent coral-fauna. Unfortunately 
the paucity of our information respecting the earliest Secondary coral-fauna, 
that of the Lower Trias, is so great that the Liassic species are still greatly 
removed from the original types. 
Corals from the Zone of Ammonites Bucklandi (bisulcatus). 
Corals are not numerous as regards their species in this zone, and the com- 
