1912] Wiegand,— Amelanchier in eastern North America 133 
Massachusetts, from Nantucket, and from several localities in Con- 
necticut. Since then apparently the same form has been collected by 
F. S. Collins at Eastham, Massachusetts. These forms certainly are 
perplexing. After a study of the herbarium material and of the plants 
growing on the Blue Hills the writer is inclined to believe that the 
small-flowered forms are hybrids between A. oblongifolia and A. 
stolonifera. The reasons for this belief are as follows:— 1. Both 
species grow upon the Blue Hills (A. oblongifolia in the damp pockets). 
2. Many plants on the Blue Hills otherwise similar to the micro- 
petalous plants have larger petals. 3. The micropetalous plants 
there differ considerably in foliage. 4. In the majority of such micro- 
petalous plants the foliage is more like that of A. stolonifera as to the 
number of the veins. 5. The herbarium specimens, collected in the 
Blue Hills, and having small petals, may be sorted into two piles, 
one with the coarser teeth of A. stolonifera and the other with the fine 
teeth of A. oblongifolia. 6. The very globular young fruit of most 
of the micropetalous plants, on which there is a very short hypan- 
thium, is exactly like that of A. oblongifolia. 7. The summit of the 
ovary is usually glabrous like that of A. oblongifolia. 8. On the 
Blue Hills the plants grow in various soils: either on exposed dry rocks 
with A. stolonifera, or in damp pockets accompanied by typical A. 
oblongifolia; on Nantucket, according to Bicknell they grow “in 
low grounds about the borders of swamps as well as on the dry moor- 
land and in pine barrens.” One of the Connecticut plants was from 
* dry ground,” another from " thin soil on ledge of rocks," and another 
from “dry sandy soil." This suggests a possible Mendelian combi- 
nation of dry and wet soil preferences. 9. Both Dr. Robinson and 
Mr. Bicknell have said that “intermediate” forms occur between var. 
micropetala and A. oblongifolia. "These might well be other Mendelian 
combinations. Intermediates of this kind are certainly quite numer- 
ous on the Blue Hills. 10. On these hills the plants are low, but 
while some have the stoloniferous habit of A. stolonifera, others have 
the cespitose habit of A. oblongifolia. 11. The summit of Great 
Blue Hill has been recently cleared and in some places burned, a con- 
dition which in Maine seems especially favorable for hybrids of Rubus, 
and in Newfoundland for hybrids of Amelanchier. 12. Between A. 
oblongifolia and A. stolonifera a distinguishing feature, in most cases, 
is the narrowness of the petals in the former species and the broadness 
in the latter species. There is often, also, in A. oblongifolia a tendency 
