Appendix 



Scheme of Classification 



Example: Man — Homo sapiens 



Phylum Chordata 



Subphyliim Craniata — Vertebrata 



Class Mammalia 



Order Primates 



Family Hominidae 



Genus Homo 



Species sapiens 



A species is the smallest standard group into which plants or animals are 

 classified. Members of a species are alike except for relatively slight, more or 

 less inconstant differences and can interbreed. A genus includes a number of 

 species that have many features in common. Similarly, a family is a group of 

 genera, an order a group of families, a class a group of orders, and finally a 

 phylum a group of classes that have fundamental likenesses. Thus the phyla 

 are the largest groups into which the plant or animal kingdom is divided. 



Throughout their history classifications have varied with the knowledge of 

 the classifier. They still vary especially in the genera and species, hence there 

 is no one true or best classification. 



The Plant Kingdom 



Several tables have been consulted and parts included in the following table; 

 especially those in T. I. Storer, General Zoology, 2nd. ed.. New York, McGraw- 

 Hill Co., 1951. C. A. Villee, Biology, 2nd. ed., Philadelphia, W. B. Saunders Co., 

 1953, and Zoological Names. Prepared for Sect. F., Am. Assoc, for the Advance- 

 ment of Science, 1949. 

 Phylum Thallophyta. The simplest plants, without true roots, stems or leaves 



(about 107,000 species). 



Subphylum Schizophyta 

 Class Bacteria 

 Class Cyanophyceae — blue-green algae. Most primitive plants. 



Subphylum Algae. Thallophytes with chlorophyll. 



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