As suggested by Peck they are both closely related to C. chimonophilus berk.
"Studies of American Fungi. Mushrooms, Edible, Poisonous, etc."
George Francis Atkinson
He is followed by Hennings, who under the same section of the genus, lists P. flavidus berk.
"Studies of American Fungi. Mushrooms, Edible, Poisonous, etc."
George Francis Atkinson
28.-Perpendicular section through Lamproderma scintillans, berk.
"The Myxomycetes of the Miami Valley, Ohio"
A. P. Morgan