o/* Ulodendron to Lepidodendron, cfcc. 133 



In regard to the significance of these Ulodendroid scars he 

 says they are the result of an unequal dichotomy of the stem, 

 the alternate dichotomies being barren or fertile — the barren 

 going to form the axis of the stem, the other to form the 

 fertile branch, from which eventually results the Ulodendroid 

 scar. The thong-like impressions, which one almost always 

 notices, especially on the upper part of the large scars, he 

 ascribes to the impressions of the leaves at the base of the 

 fertile branch. 



1871. Weiss. Fossile Flora der jiingsten Steinkohlen- 

 formation und des Kothliegenden im Saar-Rhein-Gebiete, 

 zweites Heft, p. 146. — This author does not express any 

 decided opinion on the relationship of TJlodendron to Lepido- 

 dendron, evidently preferring to leave the matter an open 

 question. 



1872. Williamson. Philosophical Transactions, vol. clxii. 

 p. 209, pi. xxvi. fig. 24; pi. xxvii. figs. 25, 26 ; pi. xxviii. 

 figs. 27, 28. — The internal structure of Ulodendron is here 

 described by Dr. Williamson, who says : " So far as all these 

 portions of its organization are concerned this Ulodendron 

 resembles the lowest type of Lepidodendron " (p. 210) ; and 

 again, " It seems probable that these scars sustained objects 

 which were chiefly developed from the epidermal layer and 

 whose base rested upon the outer bark ; they certainly were 

 not roots or branches, and I incline to the belief that they 

 were organs of fructification." 



1875. Feistmantel. " Versteinerungen der bohraischen 

 Kohlenablagerungen," Palajontographica, vol. xxiii. p. 194. 

 — Feistmantel appears to have brought together in a confused 

 manner Lepidophloios^ Lepidodendron^ and Ulodendron. Under 

 Halonia punctata^ L. & H. sp. [Bothrodendron punctatum. 

 L. & H.), is figured on pi. xlvii. a Ulodendroid stem, beneath 

 which is printed " Halonia punctata^ L. & H. Decorticated 

 state oi Lepidodendron laricinum^ Sternberg |" but this plate 

 is also mentioned in the letterpress as an illustration of Lepi- 

 dophloios laricinuSj Sternberg. On his pi. xlvi. is shown a 

 specimen of " Ulodendron majus, Sternberg (?), probably only 

 a form of Lepidodendron^ This plate is very roughly exe- 

 cuted, but from the form of the leaf-scars probably represents 

 Sigillaria discophora^ Konig, sp. {—U. majus, L. & H.). 

 His pi. xlvii. may also belong to this species j but from the 

 state of the preservation of the specimen, it is quite impossible 

 satisfactorily to settle the point. 



1875-77. Stur. Culm Flora, pp. 262, 267, 270, and 283. 

 — Stur unites Ulodendron commutatum, Schimper {=U. par- 

 matum, Carruthers), with Lepidodendron Veltheimianum, and 



