PHYTONIC VIEWS 135 
whole shoot regarded as being mainly composed of leaves, but some even 
‘contend that the axis has no real existence as a part distinct from the 
leaf bases.+ 
This view in its general form represented the leafy plant as constructed 
‘on a plan somewhat similar to that of a complex zoophyte. It has more 
recently culminated in the writings of Celakovsky and Delpino. The former 
in his theory of shoot-segments (“ Sprossgliedlehre”) starts from the position 
that the plant is composed of morphological individuals ; the cell, the shoot, 
and the plant-stock are recognised as such. The stock is composed of 
shoots and the shoot of cells. Braun recognised the shoot as the individual 
par excellence; between the cell and the shoot is a great gulf, which has 
not yet been filled; ‘‘between the cell and the bud (shoot) there must 
be intermediate steps, the limitation of which no one has succeeded in 
‘defining” ; the long sought-for individual middle step is the shoot-segment 
(Spross-glied), which is neither leaf only nor stem-segment only, but the leaf 
together with its stem-segment. Now this reasoning appears to involve a 
mistaken method of morphology ; the intermediate step mzs¢ occur ; we will, 
therefore, discover and define it. The definition of it consists in the draw- 
ing of certain transverse and longitudinal lines partitioning the shoot, lines 
which in the sporophyte have no existence in nature; the assumed necessity 
of partitioning the shoot into parts of an intermediate category between the 
whole shoot and the cell brings these assumed limits into existence. 
Notwithstanding the ingenuity of the theory as put forward by 
Celakovsky, in the absence of any structural indication of the limits of 
the shoot-segments in the vast majority of cases the theory does not appear 
to be sufficiently upheld by the facts. 
An extreme, and indeed a paradoxical position has been taken on this 
phytonic question by Delpino. As a consequence of his studies on 
phyllotaxis he concluded that the axis is simply composed of the fusion 
of the leaf-bases; that the leaves are not appendicular organs, but central 
organs; that an axis or stem-system does not exist, and accordingly that 
the higher plants are not cormophytes at all, but phyllophytes. 
The second view, that the axis and leaf are the result of differentiation 
of an indifferent branch-system, of which the limbs were originally all alike, 
has lately been brought into prominence by Potonié.? Taking his initiative, 
Ve sil Ferns, h oni 
ficoment occurrence of overtopping (© Ushergipfelung.”\mablateiSpateegiasdiaal 
lop _of certain Jj : ee 
the branching of Euccide—he—fnds—an—analogy for bis obseivationserm 
HKern-leaves,.and draws the following conclusion, that “the leaves of the. 
1 Delpino, ‘‘ Teoria generale della Filotassi.” For ref. see Bot. Jahresbr., viii., 1880, 
p. 118; also vol. xi., 1883, p. 550. 
2 Lehrbuch d. Pflanzenpalaeontologie, pp. 156-159. Also Zin Blich in die Geschichte 
a. Bot. Morph, und a. Pericaulomtheorie, 1903, p. 33, etc. It was, however, suggested 
previously by myself, PA7. Trans., 1884, part ii., p. 605. 
