92 
Geological Society. 
the locality) show the same thing, larch, birch, and other trees of 
good size being found. Freshwater and land shells are also found, 
not now living. Hence it seems reasonable to conclude that' the 
climate has become more severe, and that of the north in the days 
of the Mammoth resembled that of the south at the present time. 
The author then considered the cause of the Mammoth’s extinction. 
This he held to have been sudden. The remains must have been 
preserved soon after death. He therefore maintains that they 
were destroyed by a flood due to some sudden convulsion which 
also changed the climate. 
3. “ On the Association of Dwarf Crocodiles (Nannosuchus and 
Theriosuchus pusillus, e. g.) with the diminutive Mammals of the 
Purbeck Series. By Prof. It. Owen, C.B., F.R.S., F.G.S. 
Tho author noticed an objection which had been raised to his 
view of the origin of the differefices between the Mesozoic and 
Neozoic Crocodiles by the adaptation of the latter to the destruction 
by drowning of large mammalia (Q. J. G. S. xxxiv. p. 422), namely 
that mammals were coexistent with the Mesozoic forms, and re¬ 
marked that from their small size they would hardly constitute a 
suitable prey for the Crocodiles to which he then specially referred, 
but would be more likely to perform the same part as the Ich¬ 
neumons of the present day, which check the increase of Crocodiles 
by destroying their eggs and newly-hatched young. He stated, 
however, that in waste slabs of “ feather-bed ” marl which accom¬ 
panied the Becklesian Purbeck Collection to the British Museum, 
the remains of small Crocodiles were detected in considerable abun¬ 
dance ; and he gave a description of these, and especially of one 
which lie named Theriosuchus pusillus. This reptile, which is esti¬ 
mated to have been about 18 inches long, had scutes presenting the 
“ peg and groove ” character of those of Goniopliolis, with which 
genus it further agreed by having the antorbital part of the skull of 
the broad-faced Alligator type. In the dentition it resembled the 
Triassic Theriodonts more than any other Crocodiles. The vertebrae 
are amphiplatyan. In conclusion, the author indicated the con¬ 
ditions which have to be fulfilled in the case of recent Crocodiles to 
enable them to drown a large mammal without inconvenience to 
themselves, and showed that these conditions were realized also in 
the Neozoic forms, whilst there was no reason to suppose that any 
Mesozoic Crocodiles possessed the adaptations in question. 
November 20, 1878.—R. Etheridge, Esq., F.R.S., 
Vice-President, in the Chair. 
The following communications were read :— 
1. “ On the Upper-Greensand Coral Fauna of Haldon, Devon¬ 
shire.” By Prof. P. Martin Duncan, M.B. Bond., F.R.S., F.G.S., &c. 
The author in this paper stated that since the publication of his 
