48 NATURAL SCIENCE. Jan., 
Indies to the Gulf of Gascogny. It occurs off the East African coast, 
on the shores of the Soudan, and also in the latitudes of the Azores, 
another prolific region, yielding twelve species of Brachiopoda, of 
which four are also common to the West Indies, and eleven to 
European seas. A species dredged off the Portuguese coast, and 
named Tevebratula sub-quadvata by Gwyn Jeffreys, is now regarded by 
Fischer and Cthlert as very closely allied to Dyscolia wyvillii, and the 
same authorities recognise Terebratula (D.) guiscardiana from the Sicilian 
Pliocene as an ancestral form of this interesting family Dyscoliide. 
The authors concur with Davidson in regarding the T. septentrionalis 
couthouy, which is larger and more rounded than the elongated and 
sub-pentagonal 7. caput-serpentis, asa distinct species. They note, how- 
ever, the occurrence of the varietal form they have named T. geymana, 
from the Cape de Verde islands, and suspect it to be allied to the 
examples of so-called TJ. septentrionalis, recorded from the South 
Atlantic (Cape of Good Hope), the Indian Ocean, and Prince 
Edward’s Island (5). 
Sixteen deep-water species were obtained during the ‘‘ Talisman ”’ 
and ‘ Travailleur”’ expeditions, three of which, Ahynchonella cornea, 
Eucalathis tubevata, and E. ergastica, were previously little known (2). 
Thirteen of them, according to Messrs. Fischer and Céhlert, occur in 
a fossil condition in the Pliocene marine deposits of Sicily and 
Calabria. These species are either absolutely identical, or at least 
exhibit such slender differences as permit their describers, in calling 
them by different names, to indicate a common origin. The Zanclean 
Sands of South Italy yield an assemblage of fossil forms which 
recalls the abyssal fauna of the marine Lusitanian province. We 
learn (2) that three species, Ft. sicula, Dyscolia guiscardiana, and 
Muhifeldtia (Megerlia) granulata, have become extinct in the Mediter- 
ranean, while such closely allied forms as R. cornea, D. wyvillii, and 
M. echinata continue to be perpetuated in the Atlantic Ocean. Three 
other species found in the Pliocene of South Italy, Magellania pelonitana, 
M. euthyrva, and that widespread and interesting species Liothyris 
sphenoidea, which was long known as a fossil before it was dredged in 
the living state, appear to be absolutely on the point of extinction in 
the Mediterranean (2), although they are still represented in the broad 
Atlantic under the designations of Magellania septigera, M. cranium, and 
Tevebratula cubensis. 
Hence it is evident, the French conchologists conclude, that the 
Mediterranean has lost some of its deep-water species since the 
Pliocene period. This tendency is still manifested, and it is held to 
be associated with the gradual rise in the temperature of the Mediter- 
ranean waters which is about + 13° C., from below 183 metres down 
to the bottom. The Mediterranean now resembles an inland sea as 
compared with the Atlantic, where the temperature decreases as 
depth increases. The fact of the general uniformity of deep-water 
temperature, first established by the ‘ Challenger” explorations, 
