Survey of Plant Kingdom 119 



Reproduction may occur asexually by nonmotile carpospores produced 

 in a special structure known as a carpogonium (kar po -go' ni um) (Gr. 

 karpos, fruit; gonos, birth) . The latter is characteristic of red algae. The 

 nonmotile sperm (from the antheridia) is carried by water to the female 

 carpogonium where fertilization results in a zygote. The latter forms 

 many filaments, the tips of which form the many carpospores. In Poly- 

 siphonia, the carpospore forms a new plant which produces sporangia 

 (spor -an' ji a) (Gr. spores, spore; angos, vessel), each with four asexual 

 tetraspores (tet' ra spor) (Gr. tetra, four; sporos, spore). The nonmotile 

 tetraspores produce Polysiphonia plants either with male antheridia or 

 with female carpogonia. Because the sex cells are unlike and the egg is 

 nonmotile, the process is called oogamy. None of the sex cells, or asexual 

 reproductive cells, bear fiagella which is characteristic of red algae. 



Male orqan 



_ Reproduction 

 Conceptacle 



Fig, 33. — Red algae of the phylum Rhodophyta. A, "Irish moss" {Chondrus sp.) ; 



B, feathery thallus of Polysiphonia sp. 



Most red algae are usually attached m warmer sea waters (marine), 

 although a few species are inhabitants of fresh water. There are approx- 

 imately 2,500 species. 



Examples: Nemalion (Fig. 63), Polysiphonia (Fig. 33), and Chon- 

 drus (Fig. 33). 



General Characteristics of Fungi 



The "fungi," which include the last three phyla [Schizomycophyta, 

 Myxomycophyta, and Eumycophyta) of the Thallophytes, may be char- 

 acterized as follows: Fungi lack chlorophyll and consequently must de- 

 pend upon a heterotrophic mode of nutrition (het ero -trof ik) (Gr. 



