NO. 2158. JURASSIC FLORA FROM ALASKA— KNOWLTON. 457 



served, but so far as can be made out it is the same as in the Swedish 

 specimens. 



Occurrence. — 6700. Upper Matanuska Valley, Alaska. Crest of 

 spur between fu"st and second tributaries entering East Fork of 

 Boulder Creek above its mouth. Elevation, 4,780 feet. 



PTEROPHYLLUM EAJMAHALENSE Morris. 



Plate 80, fig. i . 



Pterophyllum rajmahalense Morris in Oldham and Morris, Foss. Fl. Gondwana 

 System, vol. 1, 1863, p. 25, pi. 13, figs. 3-5; pi. 14; pi. 18, fig. 2.— Fontaine 

 in Ward, Status Mesozoic floras of the United States, 2d paper, U. S. Geol. 

 Survey Mon. 50, 1905, p. 102, pi. 21, figs. 1-7. 



The specimen here figured, which appears to be from the basal por- 

 tion of a small leaf, I am not able to distinguish from specimens fig- 

 ured by Fontaine under the name of Pterophyllum rajamahalense 

 Morris. Fontaine's material came from Douglas County, Oregon, 

 where it is said to be one of the most abundant species present. It is 

 said to be somewhat less robust than the specimens described by Morris 

 from the Kajamahal series of India. Fontaine states that the substance 

 of the leaflets is thick and the veins are difficult to count, though by 

 close study of a great many specimens he has made out the number 

 as averaging abotit 15. In the present example the substance of the 

 leaflets is very thick and the nerves are obscm-e, almost obsolete in 

 fact, and in the figure they have been somewhat accentuated. 



The Rajamahal series of India, whence this species was first de- 

 scribed, is held to bo of Liassic age, while the Oregon locaUty is thought 

 to be of the same age as the well-kno^vn Jurassic beds at Yorkshire, 

 England — namely. Lower Oolite. According to Fontaine this species 

 is the same as that described by Heer,i under the name of PteropJiyl- 

 lum sensinovianum, from the Jurassic of Siberia. If the determination 

 of the position of the Matanuska locaUties is correct, it is another step 

 in showing that this species has been a persistent, long-lived type. 



Occurrence. — 6698. Upper Matanuska VaUey, Alaska, about f mile 

 up the next to the lowest creek entering East Fork of Boulder Creek 

 from the south. 



PTEROPHYLLUM AEQUALE (Brongniart) Nathorst. 



Plate 80, fig. 3. 



Pterophyllum aequale (Brongniart) Nathorst, Floran vid Bjuf I, Sveriges geol. 

 Medersokning, Ser. C, No. 27, 1878, p. 11; Floran vid Hoganas ock Helsing- 

 borg; Sveriges geol. Medersokning, Ser. C, No. 29, 1878, p. 18, pi. ii, fig. 13; 

 Floran vid Bjuf II; Sveriges geol. Medersokning, Ser. C, No. 33, 1879, p. 67, 

 pi. XV, figs. 6-10.— Zeiller, Fl. Foss. Tonkin, 1902, pi. 49, figs. 4-7. 



This species was originally described by Brongniart^ in 1825 from 



Hor in Scania under the name Nilssonial sequalis, and has subse- 



_^ . I 



' Heer, O., Fl. Foss. Arct., vol. 4, pt. 2 (Jura-Fl. Ostsiberiens u des Amurlandes), 1876, p. 105, pi. 24, 

 fig. 8. 

 2 Brongniart, Obs. sur. v6g. foss. de Here, Am. Sci. Nat. Paris, vol. 4, 1825, p. 219, pi. 12, fig. 6. 



