USNM 37343 Nilssonia comptula approximata Hollick  


Hollick (1930)

Pl. 6 Fig. 1




From Hollick (1930) (p. 44)

"Yukon River, north bank, about 17 miles below Nulato (original No. 33); collected by W. W. Atwood and H. M. Eakin in 1907 (lot 4639) (pl. 6, fig. 1). Yukon River, north bank, shore from 2 to 10 miles below Blatchford's mine (original No. 3AH20); collected by Arthur Hollick and Sidney Paige in 1903 (lot 3259)."


Locality Map



From Hollick (1930) (p. 44)

"Plate 6, Figure 1"

"Frond linear, narrowed and tapering at the base, about 2 centimeters in maximum width, irregularly pinnatifid below, irregularly split or dissected above, entire at and for a short distance below the rounded or emarginate apex."



From Hollick (1930) (p. 44)

"This specimen is more or less difficult to separate from Nilssonia comptula Heer (1878) (p. 19, pl. 4, figs. 10a, 11 - 15, 16?) a supposed Jurassic species from the Lena River region of Siberia, and it has seemed impossible to escape the conviction that it is merely varietally different from that species, representing a modified survival of an Asiatic Jurassic type of vegetation in the Cretaceous of Alaska.

Our specimen appears to be less dissected than the specimens of the species figured by Heer, and the basilar outline is apparently more acutely cuneate, the lower segments being more cuneate or triangular. A tendency to splitting is indicated in the marginal irregularities in several of the segments of our specimen and in Heer's Figure 10a, and it may be inferred that more or less of the apparent pinnatification shown in Heer's figures is in reality due to similar splitting or laceration of the frond.

Ward (1905) (p. 90, pl. 16, figs. 2 - 9) described and figured certain specimens from the Jurassic of Oregon that he referred to Nilssonia orientalis Heer (1878) (p. 18, pl. 4, figs. 5 - 9) in connection with which he mentioned (Ward 1905) (p. 91) the feature of "laceration that imitates original segmentation". Ward's figures are far more suggestive of our Alaska specimen than they are of Heer's figures of Nilssonia orientalis."