624 
Notes. 
production of outgrowths seems to be a response on the part of the 
plant to insufficient transpiration. 
Note. — Similar, but less well-marked, outgrowths were observed on 
the leaves of plants of Ceratotheca triloba . As in the case of Hibiscus 
vitifolius , they were not formed in a plant placed in the open ground. 
Outgrowths which may prove to be of the nature of those in Hibiscus 
vitifolius have been described by Sorauer in Dracaena ( angustifolia , 
&c.), Cassia tomentosa , Acacia ( semper florens , &c.). 
E. BALE, Cambridge. 
STEM-STRUCTURE IN SCHIZAEACEAE, GLEICHENI- 
ACEAE, AND HYMENOPHYLLACEAE h— There is a wide 
difference between the types of stem-structure shown by the different 
members of the Schizaeaceae 2 . Thus Lygodium has a stele in which 
the xylem forms a solid mass in the centre of the stem, and is 
surrounded by a continuous ring of phloem, pericycle, and endo- 
dermis. 
Aneimia Phyllitidis , on the other hand, has a ring of separate 
bundles (or steles), which may be compared with those of Aspidium 
or other Polypodiaceae ; each of them consisting of a band of xylem 
surrounded by a phloem, pericycle, and endodermis of its own. 
Mohria resembles Aneimia Phyllitidis in type. Certain species of 
Aneimia , e. g. A. mexicana, have in the internodes a complete ring 
of xylem bounded on the inner and outer side by a ring of phloem, 
pericycle, and endodermis, with a central pith, and thus resemble 
Marsilia. Schizaea has a ring of xylem surrounding a central pith, 
but no internal phloem or endodermis. 
The above four genera, which make up the Schizaeaceae , agree in 
having a stem-protoxylem, which is not well-marked, as it consists 
of elements which are not annular or spiral, and are usually not 
specially small. Lygodium , Aneimia , and Mohria are exarch ; in 
Schizaea , however, the relative position of the protoxylem has not 
been made out with certainty. 
In their main points the types of stem-structure found in the 
Schizaeaceae agree with the structures shown at successive levels in 
the stem of a ‘ seedling ’ plant of Polypodium , i. e. at successive stages 
1 Abstract of paper read before the Botanical Section of the British Association, 
Dover, Sept. 1899. 
The main structural points in this Order and the Hymenophyllaceae are de- 
scribed by Prantl, Morphol. d. Gefasskrypt., 1, 1875, and 2, 1881, Leipzig. 
