Whitesail Lake Map-Area

Fossils were collected from the canyon of the small creek just west of

Kasalka Butte near the eastern contact of the series. Two collections were made
from this locality, referred to as Slate Creek, one in 1951 and the other in
1952. These collections were studied and all identifications made by J. A.
Jeletzky of the Geological Survey. The forms identified are:

Catalogue No. 19756, collected 1951

Sonneratia (Sonneratia) ex gr. kitchini Spath
Sonneratia (Cleoniceras) ex aff. pereziana (Whiteaves )
Sonneratia sensu lato spp. indet.

irregular echinoids from the family

Spatangidae Wright, probably belong to the genus
Toxaster Agassiz
Metahamites ? sp. indet.
Pecten spp. indet.
Yoldia ? sp. indet.
Lima sp. indet.

The 1952 collection did not include any different forms and is therefore

not listed here.

Jeletzky reported on the collection as follows:

The ammonoid genus Sonneratia Bayle is accepted in the broad sense of
F. Roman (“Les ammonites Jurassique et Crétacées”, Paris, 1938).

The genus Sonneratia even in the broad sense adhered to in this report is an
exclusively Lower Albian genus, at least in the present state of our knowledge. The
same applies to its subgenus Cleoniceras. Therefore a Lower Albian stage (latest
stage of the Lower Cretaceous series) is indicated.

The individual Sonneratia forms show strong affinities with those of the Haida
formation of Queen Charlotte Islands, and the collections from Swing Peak are
believed to be equivalent in age to the lower part of that formation. In addition to
Sonneratia (Cleoniceras) ex aff. pereziana (Whiteaves) the Swing Peak collection
contains several Sonneratia forms probably identical with or closely related to as yet
undescribed forms from the Haida formation in collections of the Geological Survey.
Coarsely ribbed forms of Sonneratia (Sonneratia) ex gr. kitchini Spath are also
represented in these collections.

Some forms of Sonneratia in the Swing Peak collections appear to be closely
allied with Sonneratia ex gr. mulleri-perinismithi-stantoni, which were recently
referred to the genus Lemuroceras Spath, and to Cleoniceras ex gr. modestum
Anderson characteristic of the Huling beds of the Californian Horsetown group.
Sonneratia (“Pseudosonneratia’) ex gr. sakalava Collignon and Sonneratia (Cleoni-
ceras) besairiei Collignon of the Madagascar Albian rocks seem also to be com-
parable with some Swing Peak Sonneratia.

All of the above mentioned forms of Sonneratia related to those in the Swing
Peak collection are generally believed to be of early Albian age. The Sonneratia
fauna collected from Swing Peak was at the time the only definite record of early