YAKUTAT FOSSILS 137 
and figured with the Swiss Upper Liassic types of the species. Our 
specimen is a hollow mold of the exterior in a slaty sandstone. 
Locality. — Pogibshi Island, opposite the village of Kadiak, Alaska. 
Collectors . — G. K. Gilbert, B. K. Emerson, Charles Palache. 
Genus Palaeodictyon Heer. 
Palaeodictyon magnum laxum subsp. nov. 
pi. xv, fig. i. 
Cfr. PalcEodictyon magnum Heer, Flora Foss. Helvetiae, p. 160, taf. lxiv, 
fig. 9, 1 877. 
The remains of this plant appear as glossy, flat, irregularly convo¬ 
luted, rarely inosculating bands 2 mm. to 3 mm. wide, on fresh sur¬ 
faces of a dark slate. The bands evidently are mere fragments that 
originally may have been connected to form a very loose and irregu¬ 
larly meshed network. 
At first sight we were inclined to refer these Alaska specimens to 
Heer’s P. magnum without qualification, they being perhaps suffi¬ 
ciently like certain portions of the figure published by Heer of this 
Eocene (Flysch) species to justify their identification. Closer com¬ 
parisons, however, satisfied us that the growth of the Alaskan form 
was more irregular and very loosely reticulated, so that it seems advis¬ 
able to distinguish it as a subspecies at least. 
Locality. —Woody Island, near the village of Kadiak, Alaska. 
Collector. — W. H. Dali. 
Palaeodictyon singulare Heer. 
pi. xv, fig. 2. 
Palceodictyon singulare Heer, Urwelt der Schweiz, p. 245, taf. x, fig. 10, 
1865,-—and Flora Foss. Helvetiae, p. 160, taf. xliii, fig. 21, taf. lxiv. 
figs. 5-8, 1877. 
This delicate form is associated with P. magnum var. laxum , but 
will be distinguished at a glance by its smaller size and much closer 
intertwinings. The bands usually are a trifle less than 1 mm. wide 
and but rarely exceed that width, and they bend in and out and over 
oue another so rapidly that they appear to form a close but always 
very irregular network. 
This form has seemed to us to agree too well with some of Heer’s 
figures of P. singulare to be distinguished even as a variety. In 
Switzerland the species occurs, sometimes in association with P. mag - 
