NATIVE AND NATURALIZED PLANTS OF SOUTH CAROLINA. 353 



of the lowest forms remarkable for the spontaneous movements they 

 exhibit. 



ORDER CXL. LICHENS. LICHENES. 



Perennial plants spreading in the form of a lobed-thallus over trees, or ui)on rocks, 

 or on the ground. Some of them contain nutritious qualities, and are used in the arts 

 and in medicine. The Iceland Moss of the druggists shops (Cetraria Islandica) con- 

 tains eighty per cent, of gelatinous nutritious substance. The Tripe de Jioch; (Rock 

 Tripe) is a species of Umbilicaria, and the Eein-deer Moss is a Cladonia. Some of them 

 yield important coloring matters, and are employed in the arts. 



I have in my herbarium 258 species, collected in this State. 



ORDER CXLI. SEA WEEDS. ALG^. 



Leafless plants with no distinct axis, growing in water (fresh or salt water) and rarely 

 on trees, consisting either of simple vescicles or of articulated filaments, or of lobed 

 fronds. Many of the marine sea weeds have useful properties. The " Irish Muss " 

 (Chondrus crisi:)us) of the shops is used for its gelatine in making blanc-mange. 

 Many other species have similar qualities, and the famous edible " Swallow's-nests " 

 of the Chinese is composed of a species of Alga. 



Of the Algse found in our State, Prof. Harvey, in his " Nereis Boreali-Americana," 

 gives twenty-eight marine species found in Charleston harbor. These added to my 

 own collection, amounting to 1-10 species (composed altogether of those inhabiting 

 fresh water, trees, &c.), will give a total for the State of 168 species. 



ORDER CXLII. THE MUSHROOM FAMILY. FUNGI. 



Plants growing on dead or dying matter, — sometimes on living plants, — often on the 

 ground, deriving nutriment mostly from the substance on which they grow. Fruit 

 various in external character. Spores either naked or contained in utricles (Asci) and 

 then called Sporidia, — mostly producing a mass of threads or cells (Mycelium) from 

 which the plant grows. 



This is an immense Order, counting by the thousands ; but a small proportion of 

 which have attracted popular attention — and we cannot pretend to do more than 

 merely to indicate a few of the more prominent and conspicuous forms which affect 

 us, either for their benefits or for the evil they entail. 



They comprise a great variety of external form and size, from the larger Mushrooms 

 which we see on the ground and on trees, to the minute species which infest the 

 leaves of plants, and are scarcely visible to the naked eye. 



If the annual loss on our cultivated crops by insect depredation is estimated at mil- 

 lions of dollars, no less do the minute fungi do their part to the same effect, in tlie 

 form of rust, smut, mildew, and mould. Most growing plants— crop plants— are more 

 or less infested by these microscopic organisms, wldch injure them to some extent, and 

 frequently destroy vitality. It is only of late years that much attention has been 

 drawn to them. In fact, it is only through the superior microscopes, so much improved 

 of late, that we can form any idea of their structure and organization— and thus pro- 

 ceed in a proper manner towards their treatment. Their structure, habits and mode 

 23 



