Scientia Sinica

140 SCIENTIA SINICA Vol. V

Krejci can not appropriately be placed in the genus Lepidodendropsis.

Passing now to the question of the generic identity of the species described as Protolepidodendron? arborescens Sze!) from the Middle Devonian of Central Hunan to the genus Lep:dodendropsis, 1 deem it necessary to state that, although I have already placed this species with a query to this genus!” val. I am in complete agreement with Prof. Krausel!’*) that these specimens must be placed in the group of the “Lepidophyten unklarer Verwandtschaft” for the present (see Krausel 1937, p.533). Despite the fact that some specimens from the Middle Devonian of Central Hunan bear a superficial resemblance to the genus Lepidodendropsis'”” "), the relation of these specimens to this genus seems to require further elucidations. The same can be said for the specimens found from the Upper Devonian of Hupeh Province!”!. I am not quite prepared to agree with Prof. Jongmans'*! that this species “almost certainly belongs to Lepidodendropsis.”

Let us now turn to the species Lepidodendron aft. leeianum G. et S. (?n. sp.) from the Wutung Series of Wusih District, Kiangsu Province. This species was described by me"?! in 1936. In one of my later publications, it was regarded as a separate new species of Lepidodendron and | had named it: Lepidodendron wusthense Sze sp. nov. This species differs from the young branches of Sublep. mirabile (i.e. Lep. leeianum) in having a more distinctly preserved leaf scar in the cushions. The cushions are marked with an obtusely rounded upper end and with a distinct keel in the lower field. Prof. Jongmans!''") stated that these specimens “very much resemble Lepidodendropsis’, yet it seems to me that the species Lep. wusihense Sze is much more related to Sublepidodendron than to Lepidodendropsis, because the cushions of the species are not crowded and contiguous and are in a typically spiral arrangement (see Pl. 1, fig. 4 in this paper), i.e. the cushions of this species are absolutely not in verticillate arrangement as in the genus Lepidodendropsis. I do agree with Prof. Jongmans that there is no true Lepidodendron from the uppermost Devonian and the lowermost Carboniferous. Hel”! said for instance: “As far as I have been able to study specimens and literature, 1 am convinced that no true Lepidodendron is known from this horizon.” On the other hand, however, I do not agree with him that my Lepidodendron wusihense is a Lepidodendropsis. This is a species much more related to Sublepidodendron, and 1 would prefer to propose here the name: Subdlepidodendron wusihence (Sze) Sze n. comb.

Regarding the true relationship of Lep. lecianum G. & S. with Sublepidodendron mirabile from the Wutung Series of Kiangsu, I have in fact changed my views several times’ * *) and now I am rather inclined to the view, as I have said before'™!, that Lep. leetanum and Sublep. mirabile should probably be combined into one species as Gothan™! advocated. This is also a species much more related to Sublepidodendron than to Lepidodendropsis

on account of the distinctly spiral arrangement of the leaf-cushions. Whether