248 
Review. 
The first section of the paper treats of the course of the 
bundles from the pinnae into the rachis of the leaf and downwards 
into the petiole and leaf-base. In order that this course may be 
accurately traced, great insistance is made on following, not so- 
much the entire bundle, as the individual protoxylem-groups- 
What we most admire is the ingenuity displayed in demonstrating, 
how all the varied modes of arrangement of the bundles of the 
petiole, from the simple system of Cycas or Dioon to the highly 
complex grouping in EncepJinlartos, are merely modifications of the 
characteristic LI. The clarity and profuseness of diagrammatic 
representation of this feature are indeed charming. It seems to us 
that the writer sheds here, in his own way, a light which never 
was on any other handling of this particular subject. It is always 
exhilarating to observe simplicity reappearing out of dire complexity. 
From the resemblance of the petiolar arc of bundles in Bowenia 
to that in Angiopteris evecta, and in view of the schizogenous 
development of the mucilage-canals in both this fern and Cycads,. 
he suggests the possibility of an actual relationship between the 
latter group and Marattiaceze. 
The second section deals with the “ Flower.” The morphology' 
of the sporophyll of the cone and its parts is discussed, and the 
course and structure of the bundles as they are found both in the 
sterile lamina, in the basal stalk, and in the sporangium (ovule) 
are most carefully and interestingly described. The course and 
character of the bundles in the axis of the cone also receives 
special attention. With Solms-Laubach, Scott and ourselves the 
author agrees in regarding the vascular structure of the cone as 
more primitive and ancestral in organisation than that of the 
vegetative part of the plant. What we more particularly rejoice to 
see is the author’s recognition of a probably homological corres¬ 
pondence between the inverted or concentric strands, situated just 
outside the central cylinder of the peduncle in EncepJinlartos and 
others, not only with the “ extrafascicular ” strands in the vege¬ 
tative stem of Cycas , EncepJialartos, &c., but also with the outer 
ring or rings of the Medulloseze. 
Considerable attention is devoted to the vascular supply of the 
seed; the author describes two distinct systems: the integu- 
mental bundles, corresponding (in accordance with his acceptance 
of the ovule as the- homologue of a leaflet) to the nervation of a 
leaf-segment, and the “ perinucellary ” strands representing a 
recent addition to the vascular system and which have been 
