96 EVOLUTION OF LIFE. 
found in the same spore-case, but in the Salvinia and Azolla 
the large and small spores have their special spore-cases, 
as in the Lycopodiacee; the large spore alone develops the 
Prothallus with Archegonia and embryo-cells, the small 
spores alone producing Antheridia with spiral filaments, 
The reproduction, however, of the Horse-tail, Fern, Rhizo- 
carp, or Lycopod is always due to the contact of the spiral 
filament of the Antheridium with the embryo-cell of the 
Archegonium, the new plant growing always from a Pro- 
thallus. The Lycopodiacez appeared on the earth later 
than the Ferns, and have probably come from them, being 
closely related at the present time by intermediate forms 
(Opiogloss&). The Rhizocarpa may be regarded as aquatic 
Lycopods. The structure of the stem and reproductive 
apparatus, and the form of the embryo, are striking proofs 
of the truth of the view that the Lycopodiacez are the inter- 
mediate forms, the links uniting the Flowerless and Flow- 
ering plants. The importánce of the facts just mentioned 
will be better appreciated when the Lycopodiacez are com- 
pared with the simplest of flowering plants. We leave now 
the Flowerless plants, or Cryptogamia, and turn to the 
Flowering plants, or Phanerogamia. 
o 
PHANEROGAMIA 
Flowers, among the most beautiful of nature's works, 
are always interesting to the laity and the botanist, offering 
objects of ornament and beauty to the one, and subjects for 
study and admiration, to the other. The flower is the 
reproductive apparátus of the higher plants, made up of 
the organs by which the seed is produced, fertilized, and 
converted into the embryo plant. If we examine the 
flower of the Violet (Yellow Violet) (Fig. 130), the green 
cup-like arrangement of leaves first deserves our at- 
tention; this is known as the calyx, and the leaves com- 
