6 Seward. — On the genus Myeloxylon ( Brong .). 
Felix \ in a more recent paper, agrees with Schenk as to the 
close resemblance between Myeloxylon and Cycads : he gives 
a figure of a specimen from Westphalia, and notes the occur- 
rence of certain narrow cells in the parenchyma which he 
considers may explain those dark lines so often seen running 
through the ground-mass of Myeloxylon- petioles. Schenk 
and others prefer to regard these dark lines as accidents of 
preservation. Such specimens as I have examined lend no 
support to the suggestion of Felix. The question of the true 
nature of Myeloxylon has been fully and impartially discussed 
by Solms-Laubach 2 in his Einleitung in die Palaophytologie: 
he figures a single vascular bundle which shows more of the 
phloem preserved than in specimens previously described. 
Solms adds in a footnote an important fact in connection 
with Myeloxylon and recent Cycads : he remarks, ‘ the latest 
observations have made it probable that the Myeloxyla are 
the leaf-stalks of Medullosae.’ ‘ If this is established/ he adds, 
‘ a new and important weight will be added to the scale on 
the side of Cycadeae.’ 
In a discussion on Myeloxylon , Schenk 3 refers to William- 
son’s specimens as probably more nearly related to Marat- 
tiaceae than are those of Renault. The same author 4 , in a 
paper on Medullosct and Tubic cadis, speaks of the Myeloxylon - 
like branch of Medullosa Leuckarti referred to by Solms, and 
admits that the suggestion of Williamson and Renault as to 
the Fern-like nature of Myeloxylon may be correct, but at all 
events it must be looked upon as belonging to an extinct group. 
Mr. Kidston 5 has figured a bundle of Myeloxylon from the 
1 Felix, Untersuchungen fiber den inneren Bau Westfalischer Carbon-Pflanzen 
(Abhandl. d. K. Preuss. geolog. Landesanstalt, Berlin, 1886). 
2 Solms-Laubach, Einleitung in die Palaophytologie, p. 165, 1857 (Fossil 
Botany, p. 161, 1891). 
3 Schenk, Die fossilen Pflanzenreste, p. 45 (Handbuch der Botanik, 1888). 
4 Schenk, Ueber Medullosa , Cotta, und Tubicaulis , Cotta (Abhandl. der 
Math. phys. Classe der K. Sachs. Gesells. der Wiss., vol. XV. p. 523. Leipzig, 
1889). 
5 Kidston, R., On the fructification and internal structure of carboniferous 
Ferns in their relation to those of existing genera, with special reference to 
British palaeozoic species (Trans. Geol. Soc. Glasgow, vol. IX. Pt. 1), PI. IV. 
Fig- 45 - 
