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Shipment No.: O-81-73
Referred by: Blodgett, Robert B.
Report prepared by: Pojeta, John
Date: 11/30/1981

November 30, 1981 Mr. R. B. Blodgett
Dept. of Geology
Oregon State University
Corvallis, Oregon 97331

Dear Bob:

At long last here is your report on the McGrath A-5 Quad. clams from Alaska. Thank you very much for your patience, I apologize for not getting this to you sooner. I am now officially out of administration except for some left over odds-and-ends and it feels good to be back in science.

There is nothing among the McGrath pelecypods and rostroconchs which dasagrees with your Eifelian age and for the most part part they are garden variety genera which can be identified from the literature on the Appalachian Devonian. It is very difficult to evaluate Devonian pelecypod species, because almost monographic work has been done since the late nineteenth century. Most of the McGrath material is highly fragmentary and this also hurts species identification.

Indentification are as follows: (see faunal list)

Devonian rostroconchs are not well known either taxonomically or paleogeographically; the Mulceodens type were probably infaunal with the rostrum and third aperture probably projecting above the sediment-water interface.

There are very few articulated or "butterflied" specimens of pelecypods in these collections; most specimens are single valves indicating some transport. However, on some specimens the ornament is well preserved indicating that they were not transported far. As indicated above, the genera in these collections are widespread in North America, but it is not possible to make species level comparison.s

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1110' (of R.B. Blodgett, 1979) , Mc Grath , Long. 155 deg. 09'22"W., Lat. 62 deg. 04'30"N. SE1/4 of NW1/4 of NE1/4 of NW1/4 of Sec. 21, R. 23 N., R. 32 W., McGrath A-5 quadrangle, Alaska. Part and counterpart molds of pelecypods found in float, approximately 703 feet below the top of an unnamed Middle Devonian argillaceous limestone unit, which is approximately 1,500 feet thick. [description from letter by Robert B. Blodgett (dated Aug. 13, 1980) to John Pojeta.]
Grammysioidea sp.
79RB8 (10061-SD) , Mc Grath , Long. 155 deg. 09'23"W, Lat. 62 deg. 04'33"N. NE1/4, NW 1/4, NE1/4, NW1/4 sec. 21, T23N, R32W. Approximately 3.0 m (10 ft) thick silicified fossil horizon, the top of which is 101.5 m (333 ft) below the top of the Cheeneetnuk Limestone. (description from Rigby and Blodgett, 1983, p. 774)
Eoschizodus, probably two species
Leptodesma
Actinopteria
spinose pteriacean aff. Actinopteria, possibly a new genus
Mytilarca
Parallelodon
Goniophora
Cypricardinia
79RB9 (10062-SD) , Mc Grath , Long. 155 deg. 09'23"W, Lat. 62 deg. 04'33"N. NE1/4, NW1/4, NE1/4, NW1/4 sec. 21, T23N, R32W. Silicified fossil horizon, approximately 3.0 m (10 ft) thick, the top of which is 81.7 m (268 m) below the top of the Cheeneetnuk Limestone. (description from Rigby and Blodgett, 1983, p. 774)
schizodiform myophoriid
Leptodesma
Actinopteria
spinose pteriacean aff. Actinopteria
Mytilarca
Goniophora
cf. Cypricardinia
grammysioid
Deceptrix large species
Deceptrix small species - Fidera-like
cf. Mulceodens
79RB11 (10095-SD) , Mc Grath , Long. 155 deg. 09'25"W, Lat. 62 deg.04'40"N. NE1/4, SW1/4, SE1/4, SW1/4 sec. 16, T23N, R32W. Silicified fossil horizon, 25.3 (83 ft) below the top of the Cheeneetnuk Limestone. (description from Rigby and Blodgett, 1983, p. 774)
a small Fidera-like Deceptrix
79RB4 (10060-SD) , Mc Grath , Long. 155 deg. 07'05"W., Lat. 62 deg. 04'03"N. NE1/4, SW1/4, NW1/4, SE1/4 sec. 22, T23N, R32W. Silicified fossils recovered from talus of limestone scree slope on west side of southeastward flowing stream in section 22. (description from Rigby and Blodgett, 1983, p. 774)
spinose pteriacean aff. Actinopteria
cf. Nuculoidea, probably 2 species
cf. Mulceodens
79RB12 (10063-SD) , Mc Grath , Long. 155 deg. 07'27"W., Lat. 62 deg. 05'15"N. SE1/4,SW1/4,NE1/4,NW1/4, sec. 15, T23N, R32W, McGrath A-5 quadrangle. Rubble crop of silicified fossils just above a band of prominent white dolomite on the south side of an east-dipping slope. (description from Poncet and Blodgett, 1987, p. 1270-1271)
Deceptrix, large species
cf. Nuculoidea, one species
probably poorly preserved chelodid polyplacophoran plates