CYCADITES. 31 



for a specimen from the North German "Wealden beds, and thus 

 defined it 1 : " C. foliis pinnatis sublinearibus, pinnis numerosis 

 linearibus approximatis apice obtusiusculis medio costatis basi sub 

 dilatatis." 



He speaks of the pinnae as possessing a strong midrib, and his 

 figure shows this character very clearly. Dunker has refigured 

 Romer's original specimen, and here again the pinnae appear 

 to have a distinct median vein ; he points out that Mantell's 

 Cycadites Brongniarti 2 should be placed in the genus Nihsonia, as 

 it does not conform to the accepted definition of Cycadites. This 

 Tilgate fossil 3 is now referred to as Dioonites Brongniarti (Mant.). 



In 1852 Ettingshausen 4 obtained a portion of a cycadean 

 frond from near Teschen, in Silesia, and referred it to Rb'nier's 

 species, but at the same time expressing the opinion that it 

 represented a form intermediate between C. Brongniarti, Rom., 

 and C. Morrisianus, Dunk. This is certainly not the same species 

 as Romer's type, and should, as Schenk suggests, be placed in 

 another species ; he speaks of it as C. Heerii, Schenk, and 

 expresses the opinion that possibly C. Brongniarti, Rom., may 

 be simply a partially developed frond of C. Morrisianus. 5 Sub- 

 sequently the same author includes both C. Brongniarti and 

 C. Morrisianus as synonyms of Dioonites Dunkerianus (Gb'pp.). 

 He states that the type specimen of C. Morrisianus, Dunk., shows 

 no indication of a midrib, and must therefore be referred to Ptero- 

 phyttum, or Dioonites instead of to Cycadites. There is the same 

 absence of a median vein, according to Schenk, in the segments 

 of C. Brongniarti, Rom., and this must, therefore, be also excluded 

 from the genus Cycadites. 5 It is not quite clear if Schenk is here 

 speaking of Romer's original specimen ; if he refers to the figured 

 specimen as it appears in the illustrations of Ro'mer and Dunker, 

 the figures are certainly at variance with Schenk's description. 

 There is the same apparent contradiction between figure and 



1 Homer, F. A. (A.), Verstein. Ool. Geb. p. 9, pi. xvii. fig. 1. 



2 Dunker, loc. cit. p. 16, pi. li. fig. 4. 



s Mantell (A. 4), Geol. S.E. England, p. 238. 



4 (A. -4), Abh. k.-k. geol. Reichs. vol. i. Abtb. iii. No. 2, 1852, p. 20, 

 pi. i. fig. 9. 



5 (A. 3), Palseontographica, vol. xix. p. 7. 



6 (A. 2), p. 233. 



