Meyer, Die Stelärtheorie und die Nomenklatur zur Beschreibung etc. 149 
and includes the pericyclic and raedullary ground tissue.“ (Biindel- 
rohr ans kollateralen oder bikollateralen Leitbündeln.) 
„ Actinostele. The „monostele“ of most roots and the 
similarly constructed Stele of certain stems. It consists of alter- 
nating, or „radially“ arranged groups of xylem and phloem, sur- 
rounded by a pericycle. Pith may or may not be present.“ (Ra- 
diales Leitbündel und Plattenbündel.) 
„Atactostele. The monostele of typical Monocotyledons. 
It consists of a numbre of scattered vascular bundles imbedded in 
conjunctive ground-tissue. Also applied to the Stele of Dicotyledons 
with meristeles not arranged in a single ring. In the latter, if 
the meristeles are all of one kind, described further as homo- 
desmic, if of different kinds, as heterodesmic.“ (Bündelgruppe 
mit unregelmäßiger Anordnung.) 
„Haplostele. A simple type of Stele, frequently found in 
seedling Pteridophyta, rhizome of Hymenophyllaceae etc. It con- 
sists of an axial rod of tracheae surrounded by a ring of phloem. 
The „pericycle“ is included if differentiated from the procambium- 
strand. If central parenchyma is present, then to be described 
as a medullated haplostele.“ (Konzentrisches Zylinderbündel bezw. 
konzentrisches Rohrbündel.) 
„Solenostele. A continuous amphiphloic tube of vascular 
tissue with widely separated leaf-gaps. Pericycle present and the 
tube delimited by an external and internal endodermis.“ (Bikon- 
zentrisches Rohrbündel mit Blattlücken.) 
„ Dictyostele. A vascular tube with large „overlapping“ 
leaf-gaps, so that the whole structure becomes a network of vas- 
cular Strands or meristeles. The meristeles are concentric. This 
is closely allied to the preceding, the difference being due to the 
approximation and overlapping of the leaf-gaps. The dictyostele 
is further defined as siphonic, when the network is simple and 
tubulär, adelosiphonic when complex, i. e. ceasing to be ob- 
viously tubulär.“ (Bündelrohr mit Bündelverbindungen und ev. mit 
akzessorischen Leitbündeln.) 
„Protost eie. A stele which is supposed to be primitive 
in structure. Has been applied to both haplo- and actinostelic types.“ 
„Hysterostele. A stele which is supposed to be reduced in 
structure, e. g. in Hippuris, Potamogeton and Hottonia (aquaticstem.)“ 
„Meristele. The vascular bündle in the old sense, except 
that it does not include actino- and haplosteles as forraerly. It 
therefore applies to the vascular bundles of the stem of Dico- 
tyledons and Monocotyledons, the „concentric vascular bundles“ of 
Pteridophyta, and vascular bundles of outgoing leaf-traces and 
leaves.“ (Leitbündel.) 
Außer diesen in seiner Xomenklaturiibersicht angegebenen 
Bezeichnungen hat Brebner noch zwei, durch die er „Polystelie“ 
ersetzen will. Die Leitbündel von Frimula und Gunnera sollen 
reduzierte Eustelen sein; daher soll der Bau der Leitungsbahnen 
von Primula und Gunnera als Eumeristelie, und demgegen- 
über der einfache Farntypus als Haplomeristelie bezeichnet 
werden (1902, p. 521). 
