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with a layer of clayey soil about three inches thick and but few 

 of the plants of the year before reappeared. In 191 7 ninety-six 

 species of flowering plants were found. No fern of any kind and 

 but one little patch of moss, the latter on the ashes of a pick- 

 nicker's fire and not reaching maturity, was found. The flora 

 was distinctively a weed one with little relation to the native flora 

 on the adjacent hillside. Possibly the only plants to come from 

 the immediate vicinity were a few seedlings of the small-toothed 

 aspen, poison ivy, red-berried elder, and poke-berry, one vigorous 

 shoot of Panlotvnia in the rock wall-probably brought from the 

 rock slide at the north where two good-sized trees of the kind 

 grow — and a few heart-leaved asters. Aside from these six 

 species all the plants, including all the abundant ones, seemed to 

 have been brought from a distance. Some twenty-four species 

 have seeds definitely adapted to wind dispersal and three or four 

 are sticktights, these may have been brought in by wind and ani- 

 mals, nearly all the remainder have small seeds with no special 

 adaptation for dispersal over long distances and were apparently 

 brought either with the cinders, on the ties of the railroad, or by 

 the laborers. To the latter undoubtedly were due the fruits, 

 apple, cherry, strawberry and raspberry. An interesting case was 

 that of the Mexican tea, Chenopodium amhrosioides, that in sev- 

 eral places grew in well-defined lines of two hundred feet or 

 more along the course of the small railroad. Probably the seeds 

 had adhered to the ties and been jarred ofif where the track had 

 remained in one place for some time. In midsummer petunias 

 and morning glories of several color varieties and sweet alyssum 

 were abundant over the whole area, and in the fall numerous 

 plants of Kochia added bits of brilliant color. INIany of the indi- 

 vidual plants, having no close neighbors to crowd them, attained 

 very large size. Single plants of Panicuin capillare and P. pro- 

 liferum grew to three and four feet in height and covered from 

 ten to sixteen square feet. Late in the summer some of the 

 species were crowded by seedlings. Under one plant of Euphor- 

 bia maculata that made a mat three feet in diameter the cinders 

 were thickly covered with tiny seedlings. On one square foot 

 over two thousand were counted. 



