76 INFEEIOB OOLITE PLANTS. 



be made to an address delivered by Mr. Etberidge to tte Geological 

 Society ia 1882, in whicli several allusions are made to the 

 occurrence of Oolitic plants.' 



The microscopical investigation of oolitic grains from various 

 Jurassic rocks tas raised a question of considerable botanical 

 interest. "Wetbered^ and other authors have demonstrated the 

 presence in oolitic gi-ains of narrow tubular elements, referred to 

 the genus Oirvanella, possibly representing the remains of AlgBB 

 ■which have been instrumental in the production of this common 

 lithological character. 



INFEEIOR OOLITE (BAJOCIAN) PLANTS. 

 In a paper On some Sections in the Oolite District of Lincoln- 

 shire, Morris incidentally notes the common occurrence of the 

 fern Pecopteris polypodioides, Brongn. {= Laccopteris polypodioides), 

 near Stamford; the same author refers also to the specimens of 

 Pterophyllum from the famous Barnack quarries.' The abundance 

 of Laccopteris in the CoUyweston quarries and elsewhere was 

 pointed out by Boscawen, Ibbetson, & Moms in a note com- 

 municated to the British Association at the Oxford meeting of 

 1847.* Sharp's papers on The Oolites of Northamptonshire^ also 

 ■contain references to a few fossil plants from Kingsthoi'pe and 

 other places. Species of Inferior Oolite plants are mentioned by 

 Professor Judd in his memoir on the Geology of Eutland.^ 



GEEAT OOLITE (BATHONIAN) PLANTS. 



The Stonesfleld Slate is by far the most important sub-stage of 

 ihe Oolitic series from a botanical standpoint, excluding the Inferior 

 Oolite rocks of Yorkshire. The lowest zone of the Great Oolite 

 series in Oxfordshire and Gloucestershire takes its name from 



1 Etheridge (82). 



■> "Wethered (89), (90), (95) ; Han-is (96) ; Seward f98), p. 124, (94») ; 

 Eothpletz (91). 



3 Morris (53), p. 337. 



* Boscawen, Ibbetson, & Morris (48) . 



s Sharp (70), pp. 361, 384; (73), pp. 274, 290, 295. 



8 Judd (7S), pp. 140, 165, 276. 



