32 THINNPELDIA. 



1856. Cycadopteris Brmmiana, Zigno, Flor. foss. Oolit. vol. i. p. 155, 

 pis. xri.-xvii. 

 C. heterophylla, ibid. pi. xviii. 

 1858. ? Odontopterisjnrensis, Quenstedt, Der Jura, p. 800, pi. xcix. fig. 9. 

 1867. TJiinnfeldia rhomboidalis, Schenk, Foss. Flor. Grenz. p. 116, pi. xvii. 

 figs. 1-8. 

 T. decurrens, ibid. p. 114, pi. xxvi. figs. 1-5. 

 T. obtusa, ibid. p. 115, pi. xxvi, figs. 6-8. 

 1869. ? Lomatopterisjurensis, Schiraper, Trait, pal. veg. vol. i. p. 472. 

 Thinnfeldia decurrens, ibid. p. 495. 

 T. rhomboidalis, ibid. p. 496. 

 1873. Cycadopteris Brauniana, Saporta, Pal. Frani;. vol. i. p. 421, pi. liv. 

 fig. 5 ; pi. Ivii. figs. 3-4 ; pi. Iviii. figs. 1-5. 

 Thinnfeldia rhomboidalis, ibid. p. 343, pi. xliii. 

 Zomatopteris jurensis, ibid. pi. Iv. figs. 1-4. 

 ? TJiinnfeldia incisa, ibid. p. 348, pis. xl., xlii. 

 1880. Cf. Zomatopteris Hasina, Moriere, BuU. Soc. Linn. Normandie, 

 vol. iv. [31, p. 361, pi. iv. 

 Pachypteris (Thinnfeldia) cf. decurrens, Scbenk, and rhomboidalis, 

 Ett., Natliorst, Ofver. k. Vet.-Akad. Forb. 1880, p. 84. 

 1888. Cf. Thinnfeldia lancifoUa, Szajnocha, Sitzb. k. Akad. TViss. "Wien. 

 vol. xcviii. Abtb. 1, p. 13, 1. i. figs. 4-7. 



1893. Zomatopteris furensis. Woodward, Lias, p. 378. 



1894. Thinnfeldia rhomboidalis, Eaciborski, Flor. Kopalna, pi. xix. 



figs. 9-15. 

 1903. T. rhomboidalis, Seward, Foss. Flor. Cape Colony, p. 57, pi. viii. fig. 1. 



Frond pinnate or tipinnate ; in tlie larger examples tte pinnate 

 leaves show a tendency in the loHng of the segments to assume 

 a bipinnate habit. Kachis stout, bearing alternately disposed 

 segments attached laterally. Pinnules leathery, varying con- 

 siderably in size and shape ; those near the base of a frond may be 

 short and more or less ovate in form, ■while others are linear and 

 reach a length of rather more than 3 cm. ; apices of pinnules 

 bluntly rounded, upper margin of the lamina curves downwai'ds 

 towards the raohis, lower margin decurrent ; midrib well marked 

 in the longer segments, but in the smaller ones it dies out 

 a short distance from the base or (Text-fig. 2) is entirelj" 

 absent; secondary dichotomously branched veins spring from the 

 midrib at a very oblique angle. 



Ettingshausen defined his species Thinnfeldia rhomboidalis, 

 founded on material from the Lias of Steierdorf, as follows : — 



"Th. ramis elongatis, subalatis, striatis, folLis coriaceis, rigidis, 

 rhomboideis vel ovalibus, obtusis v. acutis, 12-20 mm. longis, 



