46 Reports and Proceedings—Geological Society of London. 
series reappeared here (which would require a most unusual uncon- 
formability). On Ben Fyn also he could find no trace of the older 
series, the rocks there, where not igneous, resembling the newer 
series, though more highly altered than it is further north. The 
paper concluded with some remarks upon the bearing of the evi- 
dence obtained from these studies upon questions of metamorphism, 
especially as regards its ‘‘ selective ”’ action. 
3. “On some Undescribed Comatule from the British Secondry 
Rocks.” By P. Herbert Carpenter, M.A., Assistant Master at Eton 
College. 
This communication contains descriptions of seven new Comatula 
from the Cretaceous and Oolitic series of Southern England, together 
with some new facts respecting the Glenotremites paradoxus of 
Goldfuss, from the Upper Chalk. This species is remarkable for 
the presence of certain characters which are very conspicuous in the 
recent Antedon Eschrichtii, and also in a new species dredged by 
the ‘Challenger’ at Heard Island in the South Atlantic, namely, the 
presence of strong ribs on the inner wall of the centrodorsal, five of 
which, interradial in position, are much more prominent than the 
rest. So far as is yet known, these features occur in no other recent 
Comatula, with the exception of one species from the South Pacific, 
in which there is a faint indication of such ribs; but they are all 
equal. Another Antedon-species is described from the Chalk of 
Sussex. It differs from Antedon paradouwus in the absence of these 
ribs, and in the shallowness of the centrodorsal cavity. 
Two species are described from the Gault of Folkestone. One is 
an Antedon with no special relations to any recent forms. It might 
have lived as well at 20 as at 500 fathoms. But the other species is 
an Actinometra, possessing certain characters only known to occur 
in species from quite shallow water, 20 fathoms or less, in the 
Philippine Islands and Malay Archipelago. The centrodorsal is a 
flat plate, nearly on a level with the surface of the radials, or some- 
times even below them, separated from them by clefts at its sides, 
and entirely devoid, not only of cirrhi, but also of cirrhus-sockets. 
This condition is only an extreme stage of the metamorphosis of the 
centrodorsal piece, which bears cirrhi for a time after its liberation 
from the larval stem; but these cirrhi eventually disappear and their 
sockets become obliterated. The ‘Challenger’ collection contains a 
series of specimens of Act. Jukesii from Torres Straits, which illus- 
trate this pomt very completely; and it is therefore of no small 
interest to find a fossil Comatula which shows one of the extreme 
stages of the metamorphosis. 
The large size of the three Antedon-species from the Chalk and 
Gault is very remarkable. Ant. paradoxus has a centrodorsal half 
as wide again as that of-any recent form; while Ant. Eschrichtii is 
the only recent species with a centrodorsal approaching the size of 
those of the other Chalk Antedon, and of that from the Gault. Acé. 
Lovéni from the Gault, however, and the older Comatule, all had 
small calices like most recent species. An elegant centrodorsal (Ant. 
rotundus) is described from the Haldon Greensand, and also two 
