34 
Oliver and Salisbury . — On the Structure and 
The only important point in which Gneiopsis differs from our seeds 
is in the presence of plumes at the apex, for which there exists no evidence 
in Conostoma ; a minor point is the very slight development of a £ tent- 
pole \ It is of course possible that even these points of difference may 
disappear as the seeds of the group become more fully understood. 
Having regard to the occurrence of Gnetopsis , which reaches from the 
Middle Coal Measures up to the Stephanian at the top of the Carboniferous 
Formation, it is a matter of no little interest to find plants with the 
Conostoma type of seed mechanism 
persisting from the Lower Coal 
Measures right on to the close of 
the Carboniferous. 
This long persistence points to 
the fact that the small lagenostome 
and large pollen-grain formed a 
combination at least as perfect as 
any other of the contemporary 
seminal arrangements of which we 
have any knowledge. 
Before leaving the subject of 
Gnetopsis it seems worthy of re- 
mark that the cupule of that seed 
presents an interesting point of 
agreement with that of Lagenostoma 
Lomaxii. After comparing the 
specimens, we are much struck 
with the close resemblance in struc- 
ture between the long tubular hairs 
with which the cupular lining of 
Gnetopsis was so abundantly pro- 
vided and those met with in con- 
siderable quantity on the cupule of 
an ovular stage of Lagenostoma , 
and more sparingly on the old effete cupules . 1 
The occurrence of similar hairs in analogous positions on the cupules 
of the two seeds, though in itself a trivial point, gains in importance when 
taken in connexion with the other features of organization which these 
seeds had in common. 
Until a detailed knowledge of the structure of the apical region of the 
testa in Gnetopsis is forthcoming, any close comparison between this region 
and the multilocular canopies of the other seeds is out of the question. The 
1 Oliver and Scott : On Lagenostoma Lomaxii . Phil. Trans., B., vol. cxcvii, PI. X, Fig. 34, h, 
and PI. VIII, Fig. 8. 
Text-FIG. 1 r. Longitudinal and transverse 
restorations of Gnetopsis elliptic a, largely hypo- 
thetical. ap. } apical appendage, bl., ‘ blow-off’. 
