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1905.|, Lagenostoma, a Type of Pterrdospermous Seed. 255 
General Conclusions. | 
As has been already indicated, three species of Zagenostoma have been 
previously described, and these are known only in the petrified condition. 
Although, in the case of the two new species discussed here, the internal 
structure of the seed is not preserved, they agree so closely in their general 
morphology with those already recorded that there can be no hesitation 
in referring them to the same genus. JL. Kidstoni approaches nearer to 
L. physoides than to either of the other species, both in point of size, and in 
the important morphological characters presented by the apical lobes. It is, 
however, easily distinguished by the smaller number of lobes, as well as by 
the absence of other external characters peculiar to that species. On the 
other hand, LZ. Sinclairi appears to agree more closely with JZ. ovoides as 
to size, and recalls also Z. Lomaai in respect to the condition of the integument 
at the apex of the seed and the presence of a “ cupule.” 
Although numerous casts or impressions of detached seed-like bodies from 
the Upper Carboniferous rocks of Britain and the Continent have been 
figured in various memoirs, I am not aware of any which may, without 
hesitation, be referred to the genus Layenostoma. There are, however, a few 
specimens described by Continental botanists, which may be mentioned in 
connection with the species under discussion here. 
In 1804, Schlotheim* figured a pinnately branched axis, on which numerous 
oval bodies, of fairly large size, and conceivably of the nature of impressions 
or casts of seeds, were attached to the secondary branches. Schlotheim 
described these bodies as “ Blasen” or “Beeren.” Potoniét has, however, 
re-examined Schlotheim’s specimen, and has come to the conclusion that the 
bodies in question are really of the nature of diseased pinnules, due either to: 
insect. or fungal agency. Other specimens figured by Gceppert,t and Geinitz$ 
are probably of a similar nature, and there is no satisfactory evidence that the 
fronds in question, for which Gutbier,|| in 1843, proposed the name Weassvtes, 
are really the fertile leaves of Odontopteris. 
There remain, however, some impressions, figured by Geinitz? in 1855, and 
* Schlotheim, ‘ Ein Beitrag zur Flora der Vorwelt,’ p. 58, Plate 13, fig. 26, 1804 ; ‘ Die 
Petrefactenkunde,’ p. 413, 1820. 
+ Potonié, ‘ Die Flora der Rothliegenden von Thiiringen,” ‘ Abhandl. K. Preuss. geol.. 
Landes,’ Neue Folge, Heft 9, Theil 2, p. 32, Plate 2, fig. 1, 1893. 
t Goeppert, ‘ Die Gattungen der Fossilen Pflanzen,’ Lief 5—6, pp. 98 and 100, Plate 6, 
1841. ‘ 
§ Geinitz and Gutbier, ‘Die Versteinerungen des Zechsteingebirges . . . Systems ip 
Sachsen,’ vol. 1, p. 21, Plate 8, fig. 8, 1848. 
|| Gutbier in Geinitz, ‘Gaa von Sachsen,’ p. 85, 1843. 
I Geinitz, ‘Die Versteinerungen der Steinkohlenformation in Sachsen,’ pp. 21 and 57, 
Plate 26, figs. 10, 10a, and 11, 1855. 
