Salih
by the Nathorstites fauna in the Peace River ‘Foothills fevours a Ladinian or
late Middle Triassic age. Indeed in recent publ ications of the Geolozical
Survey and inane in the Can aian Tisle-Naturalist more and more stress
has been laid on the Ladinian davines An endeavour has been eee hoWever,
not fev tae ere eee a stand, ani to keep the question even until
saat oeeea catia ode is available. ;

The difficulties seem to ae tereety seorra cdhical. Late Middle and
Uoper Triassic standard chronology is based mainly on the succession of
faunas in temperate and. bropagel Miatituded|on the site of ancient Tethys,
in the Alos aaa Himalayas. Nathorstites, on the other hand, has a boreal
ane and Goes ‘not eetena far south, not even far into temperate
latitudes (See Fizure Den. |

Three possible byes bona are wor th considerines: (1) the Aelbetsdl tee
fauna is ae in are to the HME radian or Protrachyceras Hr eoneieas
fauna, and is merely a eteet phase Of aati (2) Roe Hathorstites FeNne is
onuat in’ aze eS the Rare Mernian or ‘rachyceras ‘fauna, et ce merely
ea phase of it (this ae ‘been & a Agel Palen view. See lartin, +1926);
and (3) He Nation sel tee one differs in age A Sine oe Evotrachycoras
archelaus or Trachyosras fauna and possibly is intermediate in age Reieen
them: thie “imegewmraierernetsshors would ole adding a new fannie zone to the
standard Triassic Anioaaceblanls: |

In this and | earlier related reports by the writer, ne wishes to point
out, too, that comparison of species from British Colmmeie with ke in
foreign eeatiics is not =i asses. specimens of “ance Pandan species,
but with illustrations or seiomiainione of them. The validity of correlations
based on these comparisons, Prereroro Cenende to a considerable eeres on
the atcuieans of ainene: RunEGESeSeRE aa reise curacy and detail of the

descriptions.

Cerrelation-with Europe and. Asia.
The latest, Ladinian, or latest Middle Triassic, fauna is -the Protrachyceras

archelaus fauna. It has a wide distribution on the site of the ancient
Tethys seaway, for example in the Wengen beds of the South Tyrol, in the
Roten Kalke of Greece, in Bithynia, inthe. Dobrudscha area.of Rumania, in

the Daonella shale and, possibly also, Daonella limestone of Spiti, India,