W. Carrufhers — Halonia and Lepidodendron. 



151 



Salonia punctata, Geinitz, Steinkohl. in Sachs, 

 pi. iii., fig. 16. 



scars of Bergeria, and the upper or inner surface the oval openings 



in the inner bark, through 

 which the vascular bundles 

 passed to the leaves. This 

 one specimen combines in 

 itself all the forms under 

 which Halonia is found. 



The first result of this 

 determination is to show 

 that leaf scars which are 

 not those of the articulating 

 surface are worthless for 

 basing diagnoses upon. Some forms of Bergeria are forms of 

 Lepidopliloios ; others belong, as I have observed, to species of 

 Lepidodendron, in which the leaf cushions are somewhat tumid. 

 Bergeria then, and all species or genera based on scars which do 

 not show the articulating surface, must be eliminated from our lists. 

 And with Bergeria must go Halonia as a separate genus, seeing that 

 it is only a condition of Zepidophloios, and it may be of other 

 Lepidodendroid plants. Cyclocladia, of Goldenberg, being founded 

 in error on an imperfect specimen of 

 Halonia, disappears also of course with it. 

 The group of Lepidodendroid stems 

 which have large round or oval depressed 

 scars on their stems, and which form the 

 genus TJlodendron, have the rhomboidal 

 leaf scars of Bergeria. I have elsewhere 

 given my reasons for considering these 

 large impressions to have been produced 

 by aerial roots. It seems to me not im- 

 probable that TJlodendron vae^j be the main 

 stem of plants of which LepidopJdoios 

 and Halonia were the younger portions. 

 I have no doubt that Halonia was a fruit- 

 bearing branch. Lepidodendroid plants 

 had their fruits in the form of cones, — 

 that is to say, of modified branches. The 

 falling of the ripe cone would leave such 

 a scar as terminates all the tubercles. The 

 arrangement of the tubercles is very vari- 

 able. In some specimens they are arranged 

 symmetrically, but the same branch some- 

 times shows considerable differences. Such 

 a specimen exists in the Museum of the 

 Bradford Philosophical Society ; it has 

 the tubercles somewhat crowded at the 

 one end, and few and distant at the other. 

 A fine specimen from the Dudley Coal- 

 measures, now in the collection of the 



British Museum, shows the nature of the Halonia gracilis, Lindl. and Hutt. 



