WILIIAMSONIA. 



lor 



1849. Zamites taxina, Brougniart, Tableau, p. 106. 

 Z. peotinata, ibid. 



1850. Pterophylhim Fresliamim, TJnger, Gen. spec. p. 288. 

 P. taxinum, op. cit. p. 289. 



1851. Hioonites plumula, Miquel, Over Eangs. fosB. Cycad. p. 212. 

 D. taximis, ibid. 



1854. Falteozamia peotinata, Monis, Brit. Foss. p. 15. 



P. taxina, ibid. 

 1856. Dioonites plumula, Bornemann, Foss. Cycad. p. 56. 



D. taxinuf, ibid. 



1871. Palceozamia peotinata, Phillips, Oxford, p. 169, Diag. xxx. figs. 2-3. 

 P. taxina, op. cit. p. 169, Diag. xxx. iigs. 4-5. 



1872. P. peotinata, Balfour, Pal. Bot. p. 80, fig. 79. 



1873. P. pecten. Sharp, Quart. Joum. Geol. Soc. vol. xxix. p. 295. 

 Zamites peetinatus, Zigno, Flor. foss. Oolit. vol. ii. p. 37. 

 Pterophyllmn taxinum, op. cit. p. 17. 



1875. PaUeozamia peotinata, Judd, Geol. Eutland, p. 276. 

 1884. Ptilophyllimi aeutifolimn, var. j8, peotinatitm, Eichards, SjTiopsis,. 

 pp. 4-5. 

 P. aeutifolimn, var. taxinum, ibid. p. 5. 

 1894. P. aoutifolium, Woodward, Lower Ool. p. 599. 



Willia/maonia peeten, ibid. 

 1900. W. pecten, Seward, Manchester Lit. Phil. Soc. vol. iliv. p. 20, pi. iii.. 

 fig. 6. 

 W. peeten, Seward, Jurassic Flora, i. p. 190, pi. ii. fig. 7 ; pi. iii. 

 text-figs. 30-35. 



Tie original specimen of Zamia peotinata of Lindley & Hutton, 

 from Stonesfield, is in the Oxford Museum ; the specimen figured 

 by Phillips as Palxcuamia peotinata, also from Stonesfield, is in the 

 same collection. 



Localities and Horizons. — Stamford (Inferior Oolite) ; "Wansford 

 [Inferior Oolite (Lincolnshire Limestone)] ; Stonesfield [Great 

 Oolite (Stonesfield Slate)]. 



For a diagnosis and general account of the fronds of Williamsonia 

 peoten reference must be made to the Jurassio Flora, vol. i.' 



The specimen from Stamford shown in PL 511. Fig. 8- 

 undoubtedly belongs to this species ; it agrees exactly with the 

 smaller fronds from the Yorkshire plant-beds in which Williamsonia 

 pecten is exceedingly common, and is represented by fronds which 

 vary considerably in size and in the shape of the segments. 

 Lindley & Hutton refer the Stonesfield frond to Zamia peotinata 



1 Seward (00), p. 190. 



