Recent Literature. 265 



The accompanying map shows, also, the former and recent dis- 

 tribution of Salix polaris, which, in connection with the other 

 facts mentioned above, may give us important hints as to the migra- 

 tion of plants. It is to be hoped that Professor Nathorst will soon 

 give us the promised work upon the distribution of these plants. 

 And similar researches are highly recommended to the paleobotanists 

 of this country. 



Fridolin Krasser: The Rhetic flora of Persia.'^ 



It was not until the year 1858 that the fossil flora of Persia was 

 investigated, when Dr. Goebel, as a member of the Khanikow- 

 expedition to Chorassan, had the opportunity of making some col- 

 lections in that country. These were studied by Dr. Goeppert. 

 While Dr. Goebel collected in the province Asterabad in eastern 

 Persia, visited Tietze, several years later, Hif near Kaswin and the 

 mountain Siodscher, and Dr. Wiihner made extensive collections on 

 the Polak-expedition, discovering plant-bearing deposits near Rud- 

 bar and Sapuhin. 



The Persian fossils from these localities occurred in a formation 

 consisting principally of a greenish or sometimes reddish sand- 

 stone, the age of which, judging from the flora, seems to be iden- 

 tical with the Rhetic formation. 



The duthor gives a complete list of works, published upon this 

 Persian flora, the most important having been written by Goeppert, 

 Polak, Schenk, Sturr and Tietze. He also mentions the most in- 

 teresting fossil plants that were collected by the above mentioned 

 explorers, and gives, finally, a full account of a very large collec- 

 tion, made recently by Dr. Rodler near Sapuhin at Kaswin, and 

 presented to the Vienna Museum by the late Dr. Polak, court-sur- 

 geon of the Shah. It is especially from this last collection, that the 

 age of the formation has been ascertained, and the specimens seem 

 to give a more complete illustration of that flora, than any of the other 

 Persian collections. We find in the list a few Archegoniata: Eqici- 

 setacecB and Filices. Among the genera of these families are Eqiu- 

 setum, Phyllotheca, Asplenhim, Bernoicillia, Clathropteris 2ind others. 

 The Cycadece are represented by Podozamites, Otozamites — of which 

 O. Polakii is described as new to the science — and such genera as 



*"Ueber die fossile Flora der rhatischen Schichten Persiens." (Sitzungsberichte 

 d. K. Akad. d. Wissenschaften, Wien. vol. loo, 1891, 20 p.) 



