454 PHARMACEUTICAL BOTANY 
Outuine oF Lire History or Pinus Strosus 
Oéspore 
Embryo (Young Sporophyte)—(see 1) 
7 Seedling Sporophyte (Composed of hypocotyl, cotyledons, 
tap root, first leaf and bud) 
Mature Sporophyte............. (see 2) 
Staminate Cones hides ay Carpellate Cones 
Microsporophylls (stamens) Megasporophylls (carpels) 
Megasorus (Ovule) (see 3) 
Microsporangium (Spore case) Megasporangium (nucellus) 
Megaspore mother cell 
Microspore-mother-cell Megaspore (Embryo sac) 
Microspore (Pollen grain) Prothallus (Endosperm tissue) 
Male Gametophyte (see 4) Female Gametophyte (see 5) 
Pollination (transfer of pollen) Archegonium 
sy , oan 
One of Sperm Nuclei Ovum—egg nucleus 
(Fertilization) 
— Oéspore— 
Embryo and “‘suspensor” in seed 
1. Embryo is in a seed structure composed of a seed coat (developed from the 
integument of the ovule, “‘megasorus’’) enclosing perisperm (developed from mega- 
sporangial tissue, the nucellus). The perisperm surrounds endosperm (prothallial 
tissue developed in embryo sac) and within the endosperm is the embryo which was 
developed from a fertilized ovule within one of the archegonia. The seed wings 
are developed from a portion of the scale leaf (ovuliferous scale or megasporophyll). 
‘2. Mature Sporophyte consists of a root system, trunk, lateral branches, spur 
shoots bearing foliage leaves in fascicles. Staminate cones are borne at base of 
new growth. Carpellate cones are borne at end of a lateral axillary branch. 
3. Megasorus or ovule is composed of an integument surrounding the mega- 
sporangium (nucellus) except at apex where the micropyle (opening) leads to 
pollen chamber. 
4. Male Gametophyte—consists of the mature pollen grain containing two pro- 
thallial cells, a tube nucleus and a generative cell. 
5. Female Gametophyte consists of prothallial tissue (endosperm) with eee 
archegonia, each containing an ovum. It is the mature “embryo sac.” 
