682 - Appendix 7 



ally terrestrial, plants, with regular alterna- 

 tion of generations; the sporophyte always 

 dependent on the gametophyte; lack true 

 vascular tissues (xylem and phloem). (23,000 

 species.) 



Class Hepatkae: the liverworts; usually 

 simple, flat plants without stem or leaves. 



Class Mitsci: the mosses. 



Class Anthocerotae: the hornworts. 



Phylum TRACHEOPHVTA: true vascular 

 plants, having definite xylem and phloem 

 tissues. (265,000 species.) 



Subphylum psilopsida: a mainly extinct 

 group of leafless, rootless, vascular plants. 



Subphylum lycopsida: the modern club 

 mosses belong to this largely extinct group; 

 having simple conducting tissues, poor roots, 

 and very small green leaves. 



Subphylum sphenopsida: the horsetails are 

 the modern representatives of this previously 

 abundant group; stems display joints and the 

 leaves are small and scalelike; simple con- 

 ducting tissues. 



Subphylum pteropsida: well-adapted land 

 plants, with complex vascular tissues, an ex- 

 cellent root system, and large, conspicuous 

 leaves. 



Class Filicinae: the ferns and related forms; 

 numerous extinct as well as living species. 



Class Gymnospermae; conifers, cycads, etc.; 

 no ovule case or true flowers; no fruits. 



Class Angiospermae: flowering plants; 

 ovules completely enclosed in an ovule case; 

 seeds enclosed within a fruit. 



Subclass Monocotyledoneae: grasses, lilies, 

 orchids, etc.; embryo with a single cotyledon; 

 vascular bundles scattered through the stem; 

 leaves with parallel veins; flower parts in 

 threes or sixes. 



Subclass Dicotyledoneae: flowering plants; 

 embryo with two cotyledons; vascular bun- 

 dles in a ring in the stem; leaves with netlike 

 venation; flower parts in fours or fives. 



Kingdom ANIMALIA 



Organisms usually without rigid cell walls or 

 chlorophyll; nutrition usually holozoic. 



Phylum PROTOZOA: unicellular or simple 

 colonial animals, usually with distinct nu- 

 cleus and cytoplasm; with or without sexual 

 reproduction. (20,000 species.) 



Class Mastigophora: the flagellates. 



Class Sarcodina: protozoans with pseudo- 

 podia. 



Class Ciliophora: protozoans -with cilia. 



Class Sporozoa: parasitic protozoans, usu- 

 ally without locomotive or digestive organs. 



All the following phyla, consisting of mul- 

 ticellular animals, are called collectively 

 Metazoa: tlie group's Piotozoa and Metazoa 

 are sometimes called subhingdoms. 



Phylum PORIFERA: the sponges; simple 

 multicellular animals with branched or un- 

 branched, tubular body, perforated by many 

 pores that admit water containing food par- 

 ticles. (1000 species.) 



Pin lum COELENTERATA: radially sym- 

 metrical, diploblastic ("two-layered") ani- 

 mals; possess nematoevsts. (5000 species.) 



Class Hydrozoa: hydralike animals, often 

 colonial, and often having a regular alterna- 

 tion of asexual and sexual generations. 



Class Scyphozoa: jelh fishes. 



Class Anthozoa or (Actinozoa): sea ane- 

 mones and corals. 



Phylum CtenophorA: the comb jellies 

 and sea walnuts; jelhfishlike animals, some- 

 what more complex in structure than the 

 typical coelenterates; possess eight bands of 

 cilia, for locomotion. 



Phylum PLATYHELMINTHES: the flat- 

 worms; bilaterally symmetrical, triploblastic 

 ("three-layered") animals, without a true 

 body cavity or anus; excretion by means of 

 flame cells. (6000 species.) 



Class Turbellaria: nonparasitic flatworms. 



Class Trematoda: the flukes, parasitic flat- 

 worms with an enteron. 



Class Cestoidea: the tapeworms, parasitic 

 flatworms with no enteron, absorbing nour- 

 ishment through the body surface. 



Phylum NEMERTINEA: the proboscis 

 worms; nonparasitic, usually marine animals 

 with a complete digestive tract and a pro- 

 trusible proboscis armed with a hook for 



