52 F. II. Knowlton — Jv,rassic Flora of Oregon. 



There are a few species in the Pacific Coast flora that have 

 heretofore been found only in okler beds. Thus, Pterophyllum 

 rajrnahalense was first found in tlie Eajmahal series of India, 

 which is held to be of Liassic age, but as this does not differ 

 apparently from Heer's Pterophyllum sensinovianuvi from 

 the Jurassic of Siberia, if Heer's conclusion as to the age of 

 the strata containing it is correct, it appears to liave persisted 

 into the Lower Oolite. It is one of the most important and 

 abundant forms at a nundier of the Oregon localities, occur- 

 ring literally in hundreds of specimens. 



Another species regarded by Fontaine as possibly common 

 to the Rajmahal series is CladojMehis indica., though it is 

 represented by a single example and thus is not of great 

 importance, and the variety of Didymosoxirus hindrabundensis 

 is but a slight variation from the species as known from these 

 beds ; it is also represented by a small fragment only. 



The following species ai-e believed to be common to the 

 Khaetic of Sweden : JSfilsonia pterophylloides and Pterophyl- 

 lum (Bquale, while portions of a plant have been identiiied as 

 Baiera tnultifida ? from the older Mesozoic (Rhaetic) of 

 Virginia. 



From this it appears that a few of the forms had their 

 origin in older beds and persisted into this stage of the Juras- 

 sic, but none of those above enumerated is known to continue 

 into higher horizons. 



Having considered those species evidently older, it will be 

 of interest to enumerate those continuing above the Jurassic. 

 The following species have been found in Wealden, Neocomiau, 

 or higher beds : 



Onychiopsis psilotoides 

 Rtiffordia Gopperti 

 Podozamites lanceolatus 



Ginkgo siberica or digitata 

 Sequoia Iteichenbachi. 



The species first mentioned, which was doubtfully identified 

 in the beds at Big Bar, is a common species of the English 

 Wealden, and forms suggestive of it, though they have often 

 been given other names, occur in the lower Potomac of Vir- 

 ginia, the Cenomanian of Niederschona, etc. Ruffordia 

 Gopperti is likewise found in the Wealden of England. 

 Podozamites lanceolatus, as Professor Fontaine has pointed 

 out, is " probably a much abused type of leaf. It probably is 

 not a species, bnt rather a type of leaf found in many species 

 which lived in Jurassic times. The original is from the Lower 

 Oolite and the form is probably more characteristic of that 

 period than any other." Leaves that have been identified as 



