30 ARKIV FÖR BOTANIK. BAND 13. N:0 7. 



Nilssonia fallax Nath. 



Pl. 4; pl. 5, figs. 1—4. 



» Ano7nozamites-hkt blad, men med o förgrenade nerver» {» Anomozainites- 

 like leaf, but with simple veins»), Nathorst: Om de växtförande lagren i 

 Skånes kolförande bildningar etc. Geol. Fören. Stockholm Förh. Bd 5. 

 1880. P. 284. 



Anomozaniites, Nathokst: Jordens historia. Del. 2. 1893 P. 851. 



Nilssonia fallax n. sp. [allied to A'^. schaumburgensis (Dunk.) Nath.], 

 Nathorst: Über die Gattung Nilssonia Brongn. K. Svenska Vet. Akad. 

 Handl- Bd 43. N:o 12. 1909. P. 27. — Les depots mésozoiques précré- 

 tacés de la Scanie. Geol. Fören. Stockholm Förh. Bd 32. H. 3. 1910. 

 P. 514. 



Nilssonia jallax Nath. is the commonest as well as the 

 best preserved of all the plants at Kurremölla. It was dis- 

 covered, in fragmentary specimens, by Prof. Nathorst in 

 1876, and was first referred by him to Anomozamites, though 

 with the remark that the veins are simple. Since better ma- 

 terial had been procured, especially by Prof. Moberg, Prof. 

 Nathorst was able to state, in 1909, that the plant is a 

 Nilssonia. It was referred by him to a new species, N. 

 jallax, with the remark that it might be regarded as a fore- 

 runner to N. schaumburgensis of the Wealden, but it has not 

 hitherto been described or figured. 



Frond pinnate, linear, mostly 1 — 3 cm. broad and at 

 least 10 cm. long, gradually tapered towards the base and 

 more rapidly contracted towards the apex. The lamina is 

 dissected into more or less regular segments, which are at- 

 tached by the whole of their bases to the upper surface of the 

 rachis. The segments vary much in breadth, but are usually 

 rhombic to oblong, more or less obliquely truncate or round- 

 ed at the apex. The veins are parallel, mostly simple, only 

 in single cases bifurcating (pl. 4, fig. 6) or joining each other 

 towards the apex. Their number is 15—25, usually 20, in a 

 centimetre. 



The habit is very like that of an Anomozamites of the 

 type of A. minor or A. gracilis, though the veins, as already 

 mentioned, are normally simple. The attachment of the 

 segments to the upper surface of the rachis, however, clearly 

 demonstrates the iVi755oma-character (pl. 4, figs. 9 and 10). 

 The shape of the apex, as shown in pl. 4, fig. 7, also shows 

 the characteristic habit of that genus. 



