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epidemics occurred in 1893-1894 and the second began in late 1929, 

 reached its peak in 1931-1932, and persisted through to 1935 and 

 later. C. Cottam in Rhodora 36: 261 and 37: 269 et seq., has given 

 graphic descriptions of these periods of scarcity and epidemic. 

 The 1929-1935 epidemic is thought to have been caused by a proto- 

 zoon of the genus Labyrinthula. Cottam reports that at about mid- 

 summer in 1931 in most localities from New England to North 

 Carolina the leaves of the eel-grass became somewhat darkened, 

 broke from the stems of the plant, and washed ashore in great 

 windrows. Before the summer was over less than one percent of a 

 normal stand persisted in most affected areas. The Canadian coast 

 south of the Gulf of St. Lawrence was denuded by the fall of 1932 

 and when ice cleared away in the spring of 1933 practically the 

 entire area of the plant's regular range in that region was 99 percent 

 destroyed. Since 1935 the plant has slowly been making a come- 

 back into the areas which it formerly inhabited, much to the relief 

 of lovers of our wild fowl, for it is a favorite food of plant-eating 

 water fowl. 



In the waters adjacent to Florida and Louisiana and from there 

 southward in the Gulf of Mexico and the Caribbean Sea and in the 

 waters of tropical South America is found Thalassia testudimmi, 

 known popularly as "turtle-grass" or "sea-weed". Dr. J. K. Small 

 has written [Man. SE. Fl. 29. 1933] that this plant "occurs mainly 

 in vast submarine fields, often forming a dense turf. The leaves are 

 washed ashore in vast quantities and are gathered as 'seaweed' for 

 fertilizer. Only during quiet weather, and consequently clear water, 

 can one get an adequate view of these submarine fields, which are 

 favorite rendevous for various kinds of fish, turtles, and other 

 marine animals". Two other species, T. hemprichii and T. indica, 

 inhabit the waters of the Pacific and Indian Oceans in the general 

 region of tropical Asia. 



The genus Ruppia inhabits salt and brackish water along sea- 

 coasts and also the ocean floor in quiet bays, coves, and river- 

 mouths. Its commonest representative is R. maritima, known com- 

 monly as "ditch-grass", "tassel-pondweed", or "sea-grass", and 

 found throughout the temperate and tropical portions of the earth 

 in favorable situations. Other species include R. rostellata in the 

 seas of Europe and tropical Asia, R. intermedia in Scandinavian 

 waters, R. aostcroidcs originally found off Sicily, but probably 



