234 BRYOPHYTA. [CH. 



that the general appearance and mode of occurrence of the 

 specimens suggest a liverwort rather thau an alga, and proposed 

 the substitution of the genus Marchantites^. It would, however, 

 be unwise to speak with any great confidence as to the real 

 affinities of the fossil. 



The example shown in the figure is the type-specimen 

 of Leckenby^ : the breadth of the branches is about 3 mm. 

 Under a low magnifying power the surface shows distinct and 

 somewhat oblique wrinklings, the general appearance being very 

 similar to that of some recent forms of the genus Marchantia. 



A closely allied species has recently been described from 

 the Wealden beds of Ecclesbourne, near Hastings, on the 

 Sussex coast, as Marchantifes Zeilleri Sew.^- 



In a recent monograph on Jurassic plants from Poland, 

 apparently containing much that is of the greatest value, but 

 which is unfortunately written in the Polish language, Raci- 

 borski^ describes a new species of thalloid Liverwort under the 

 name oi Paleohepatica Rostafinski. The specimens are barren 

 plants larger than any Jurassic species hitherto described ; they 

 agree closely in habit with Saporta's Tertiary species Marchan- 

 tites Sezmmensis. 



2. Marchantites Sezannensis Saporta. Fig. 50. The body is 

 broadly linear and dichotomously branched, with a somewhat 

 undulating margin. Midrib on the dorsal surface depressed, but 

 more prominent on the ventral surface. The upper surface is 

 divided into hexagonal areas, in each of which occurs a central 

 pore. There are two rows of scales along the median line on 

 the lower surface. Stalked male receptacles. 



Brongniart^ first mentioned this fossil hepatic, which was 

 found in the calcareous travertine of Sezanne of Oligocene age 

 in the Province of Marne. The specimens figured by Saporta® 

 show very clearly the characters of one of the Marchantiaceae, 



1 Seward (942) p, 17, 2 Leckenby (64) PI. xi. fig. 3. 



3 Seward loc. cit. p. 18, PI. i. fig. 3. 



* Eaciborski (94) p. 10, PI. vii. figs. 1—3. 



5 Brongniart (49) p. 12. 



6 Saporta (68) p. 308, PI. i. figs. 1—8. Vide also Watelet (66) p. 40, PI. xi. 

 fig. 6. 



