264 PENNYPACKER— ON THE BEACH PLUM 



long usually in 3 or 4 flowered umbels, sepals ovate, rounded 

 at the apex, green, pubescent, calyx tube campanulate 2 

 mm. deep, glandular on the inner surface, pubescent on 

 the outer; petals white, ovate, rounded at the apex, con- 

 tracted at the base into short claws; stamens 30, from 5 

 to 10 mm. long, glabrous, inserted on the calyx tube; 

 style 10 mm. long, glabrous, with truncate stigma; carpels 

 simple, ellipsoid, glabrous. 

 Fruit Ripening August 10 to 30, of a deep yellow color, spherical 



to slightly flattened at the blossom end, 14 x 13 mm. 

 covered with a Hght waxen bloom, flecked with numerous 

 light colored spots; weight 1.45 to 1.85 grams, flesh of a 

 watery yellow color, pulp decidedly free from the stone, 

 sweet and pleasant, tannin layer slight; stone oval, slightly 

 compressed, yellowish in color, 8.5 mm. long and 7.0 x 6.0 

 mm. thick, weight .25 to .35 grams, slightly ridged on 

 the ventral, slightly grooved on the dorsal suture. 



IV. Economic Value 



One is immediately impressed, on seeing the vast expanse of P. mari- 

 tima growing on the sandy soils of the Atlantic coast, and fruiting in 

 abundance, by the thought that it should have a high economic value. 

 The characters which would seem to warrant its horticultural possibiU- 

 ties are its great hardiness, late blooming, enormous productiveness, 

 and ability to withstand adverse conditions. These were recognized 

 by Burbank several years ago and every effort was made by him to 

 cross it with some of the larger and finer species. This cross, however, 

 was not effected for several years because the Beach Plum blossoms 

 very late, long after all other plums have shed their bloom. Burbank 

 early recognized the value of the introduction of foreign blood into the 

 plum family, and from his hybridizing experiments — commenced in 

 1885 and continued up to the present time — has produced 65 varieties. 

 Of these, 38 have been developed from Asiatic, 14 from American, and 

 13 from European stock. 



It is interesting to note, that of the six American species of Prunus 

 used in his experiments, maritima should have proved to be the most 

 important, as it is the one to which the greatest interest is attached. Of 

 the American species used all are unusually hardy. Cold does them 

 no harm even in the most northern parts of the United States. It 



