1912] Hill,— The Sand Plum in Indiana 197 
parent stem in some cases, it seemed well equipped for propagation 
even if lacking fruit. But it has been examined every season for 
fruit, though not for flowers, without avail till the present. This year 
(1912) it was abundant, the greater part of the mature shrubs being 
in bearing. It varied somewhat in size and shape, but no more than 
is seen in the fruit of P. Americana. The season lasts three or four 
weeks, beginning about the middle of July. "The plums are bright red, 
without bloom, globose, 7-10 mm. in diameter, or larger and slightly 
lengthened on some shrubs. The skin is firm but not thick, flesh 
yellow and pleasantly acid, stone ovoid to oval, rather large and thick, 
the surface rugose. It was apparently an improvement on the sand- 
plum of the west, approaching the Chickasaw plum. In a climate 
with a greater and more evenly distributed rainfall, changes for the 
better might be expected. "There were a few cases in which the shrubs 
were more tree-like in form, reaching a height of four meters, but the 
mass of them was low, the trunks 3-10 dm. high. "The points in which 
it approaches P. angustifolia may be an argument in favor of its 
varietal character. 
To account for the plums I had gone back to the time when I had 
noticed manure spread on both sides of the railway track through the 
dune region. From its appearance it evidently came from the stock- 
yards of Chicago or from stock cars. It was apparently done to 
encourage the growth of some covering for the sand. This was about 
1890. It is not uncommon to find western plants springing up in the 
dump from stock cars, some of them persisting and becoming members 
of our flora. It seemed altogether probable that the plum had been 
introduced then, spread beyond the fence, and though destroyed 
within the enclosure by continual cutting, had held on outside. My 
conjecture was unexpectedly corroborated the day the fruit was found. 
Seeing some trackmen at work close by I asked their overseer if he had 
lived in the vicinity for a number of years. Learning that he had I 
questioned him about the plums. He said that manure from the 
stockyards had been spread beside the track about twenty years before, 
and the plums came up just after. As I had given him no hint of my 
conjecture, this proved strong evidenceinitsfavor. His knowledge of 
the character of the plum and of previous fruiting was shown by a 
further statement that he had transferred some to his yard but did 
not think them worth cultivating, they were so low and bushy and the 
stone was large in proportion to the flesh. 
