FOREIGN COBUESPONDBNCE. 
123 
The age of the Stouesfield fossils, nevertheless, remained for a time 
an object of doubt, when a new discovery rendered extremely probable 
the antiquity which their natural position in the earth's crust assigned 
to them. The discovery in question was made in the Purbeck- 
beds, which, belonging to the upper Oolitic serits, lie between the 
cretaceous formation and the Stonesfield strata. Fourteen species 
of mammalia, belonging to eight or nine genera (^tipalacotherium, 
Triconodon, Flagiaulax, (tc.) were found there. 
Such was the state of things when another discovery was added to 
those of which the authenticity had been so much questioned, and 
obliged us to place the date of the first appearance of mammalia con- 
siderably farther back. It was made by M. Plieuinger, who found 
at Stuttgard some minute teeth of a new fossil mammal, a type of a 
new genus, that of Microlestes, which he discovered at the junction of 
the Triassic and the Liassic strata. Hence, the Microlestes is considerably 
more ancient than the Stouesfield fossils.* 
If any doubts still remain, however, concerning this great anti- 
quity of mammalia, they will perhaps be dissipated by a letter which 
Mr. Pentland has just addressed to M. Elie de Beaumont. 
" It will be interesting to know," writes Mr. Peutland,t " that there 
have just been discovered in the 'Boue-Bed ' of Dundry, near Bristol, J 
which belongs to the superior Triassic beds, some indubitable remains 
of mammalia belonging to the family of Iiisectivora, and which Owen 
is inclined to connect with the genus Microlestes of M. Plieuinger, 
formerly discovered in Germany. It is believed that their true posi- 
tion is of more, ancient date than the Lias, and they are certainly the 
most ancient fossil mammalia known to palseontologists." 
M. Elie de Beaumont observes that one doubt only can prevail con- 
cerning the geological age of the " Boue-Bed " of Dundry ; it is, 
whether this bone-bed is really part of the Trias, or whether it consti- 
tutes, on the contrary, the first stratum of the Lias which cover's the 
former. However this may be, the discovery made at Dundry entirely 
confirms that made at Stuttgard. "Thus it is," says M. Elie de 
Beaumont, " that the pi'ogress of observation, whilst multiplying in 
so surprising a manner the mammalia of the tertiary formations, 
shows us that they penetrate, though in much smaller numbers, and 
of much smaller size, into the secondary strata, where they reach, to 
say the least, as far as the base of the Jurassic rocks, and where pro- 
bably they will not stop. These new discoveries of fossil mammals 
I * The Dromother'tum srjlvestre of Dr. Emmons is another of these "oldest" 
mammals ; and two or three jaws have been obtained from the shales associated 
with coal-beds m North Carolma, which are certainly of Triassic, and possibly 
Permian age ! — Ed. Geol. 
+ His letter is here translated from the Frencli. 
t By Mr. Charles Moore, F.G.S., of Bath. See "Siluria," new edit. p. 514. 
Sir Roderick Murcliison says these remains were found " in an agglomerate which 
fills the fissures of the carboniferous limestone near Frome, Somersetshire ; " 
meaning thereby,' we believe, what is usually known as "the dolomitic conglo- 
merate." — Ed. Geol. 
