THE AUSTRALIAN NATURALIST. 209 
ies seem to be fully formed, thus the latter kind 
‘show a tendency to become what is known as ‘‘hercogamous,”’ 
that is to say, the apparently hermaphrodite flowers have 
some peculiar structural or physiological peculiarity, which 
prevents fertilization. 
Similar dimorphic conditions in species have been 
noted in Great Britain, by-Charles Darwin, who has published 
some very interesting observations in connection with certain 
species of Primula, 
Some few years ago I found that some plants of Lepyro- 
dia scariosa, which belongs to the family Restiaceae, had her- 
maphrodite flowers, while other plants had only male or 
female flowers. This may be regarded as a polymorphic 
species, or, perhaps some would prefer to call it *‘polyoecious.’’ 
It has long been known that the cultivated strawberry, 
has different kinds of flowers, and necessitated careful atten- 
tion being paid to the different kinds in forming new planta- 
tions, so as to get the best results. 
Some plants have pistillate flowers with imperfect stam- 
ens, some have staminate flowers with imperfect pistils, others 
have hermaphrodite flowers (stamens and pistils perfect in 
each flower), while a fourth kind have staminate and _pistil- 
late flowers on the same individual plant. 
Abnormal Variations.—lt not infrequently happens that 
certain parts of a plant have peculiar growths, such as swol- 
len or distorted branches, or corollas, or the leaves may be 
more or less disfigured with numerous pustules, or striations. 
These are what may be termed ‘‘Abnormal growths,’’ and in 
a number of instances are induced by fungus or insect pests. 
The ‘hyphae of fungus growing in the intercellular 
spaces among the palisade and pulp parenchyma cells, 
frequently cause these peculiar distortions, and _ ulti- 
mately rupture the epidermis of leaves, such as we 
see in the common Flat Weed (Hypochaeris) infested with 
Puceinia hypochaeridis, and the common Couch; Grass Cyno- 
don dactylon) infested with a smut (Vstilago cynodontis). In 
the same way, the hyphae of other fungi cause distortions in 
the solid wood, such as we see in several Acacias, caused by 
the Gall Fungus (Uromycladium), and many other trees by 
the ‘“‘Bracket Fungi,’’ such as omes and Polyporus. 
Variegation.—There is another form of variation fre- 
qently met with in cultivated plants, and occasionally in wild 
plants. A few months ago my attention was drawn to a 
branch of Brachylaena neriifolia, in a plantation in the Bo- 
tanic Gardens, near the sea wall, having beautiful variega- 
ted leaves. I suggested that the branch should be layered, 
and the result is a beautiful plant has been separated and 
is now growing in a, flower pot. 
Leafy Spikelets in Grasses (so-called Viviparous growth) : 
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