42 DIOONITES. 



Dioonites Dunkerianus (Goppert). 



[PI. II. Fig. 3; PI. III. Fig. 6.] 



1843. Nilssonia pecten, Dunker, Progr. p. 7. 



Pterophyllum Dunkerianum, Goppert, Foss. Cycad. p. 52. 

 1846. Pterophyllum Dunkerianum, Dunker, "Wealdenbildung, p. 14, pi. ii. 

 fig. 3, pi. vi. fig. 4. 



Cycadites Morrisianus, Dunker, ibid. p. 16, pi. vii. fig. 1. 



? Pterophyllum abietinum, Dunker, ibid. p. 15, pi. vii. fig. 2. 



1848. Pterophyllum Dunkerianum, Bronn, Index pal. nomencl. p. 1055. 

 Cycadites Morrisianus, Bronn, ibid. p. 371. 



1849. Zamites Dunkerianus, Bronguiart, Tableau, p. 107. 

 Cycadites Morrisianus, Bronguiart, ibid. p. 107. 



1850. Pterophyllum Dunkeriamim, Unger, Gen. spec, plant, foss. p. 290. 

 Cycadites Morrisianus, linger, ibid. p. 280. 



1851. Dioonites Dunkerianus, Miquel, Rangschik. foss. Cycad. p. 212. 

 ? Dioonites abietinus, Miquel, ibid. p. 205. 



1852. Pterophyllum Dunkerianum, Ettingshausen, Abh. k.-k. geol. Reichs. 



vol. i. Abth. iii. No. 2, p. 20. 

 1856. Dioonites Dunkerianus, Bornemann, Organ. Rest. Lettenkohl. p. 56. 



Cycadites Morrisianus, Bornemann, ibid. p. 51. 

 1869. Dioonites Dunkerianus, Schiniper, Trait, pal. veg. vol. ii. p. 150. 



Cycadites Morrisianus, Schiniper, ibid. p. 180. 



1871. Dioonites Dunkerianus, Schenk, Pala3ontographica, vol. xix. p. 232, 

 pi. xxxvi. figs. 1-5. 



Cycadites Morrisianus, Schenk, ibid. p. 233. 



? Dioonites abietinus, Schenk, ibid. p. 234, pi. xxxvii. fig. 1. 

 1874. Dioonites Dunkerianus, Schiniper, loc. cit. vol. iii. p. 550. 



Type. Portions of fronds. Berlin Museum. 



Goppert 1 thus defines the species: " Pt. fronde pinnata, pinnis 

 crassiusculis alternis lineari - acicularibus elongatis pectinato- 

 patentissiinis subremotis aeque distantibus 4-5 nervis subacutis." 

 Dunker originally named this plant Nilssonia pecten, but an 

 inspection of drawings received fiom Dunker led Goppert to dissent 

 from the original designation. Dunker, in his Wealdenbildung 

 makes one or two slight alterations in Gb'ppert's diagnosis ; he 

 speaks of the venation as "nervis 3-4 instinctis," and adds "rhachi 

 crassa compressa." 2 The specimen represented in Dunker's pi. v. 



1 (1), P- 134. 

 ' (A. 2), p. 14. 



