22 
and eastern Texas is the home of this tree, which often covers large, 
often submerged areas, and is sufficiently common, when the trees are 
covered with flowers, to be a conspicuous feature in the landscape. 
Seedlings of this tree have been raised several times at the Arboretum 
but have not proved hardy. The other species of the group Brachy- 
acanthae, Crataegus saligna, is ccmmcn on the banks of streams at high 
altitudes on both slopes of the Continental Divide in Colorado where it 
is particularly conspicuous in early autumn from the brilliant orange 
and scarlet colors of the leaves. This plant has been raised several 
times at the Arboretum but has not yet established itself here. Such 
failures are probably due to accident for there seems to be no reason 
why Crataegus saligna should not grow as well in the Arboretum as 
the other Colorado species. 
The distribution of the different groups of the American species is 
interesting. The most widely and generally distributed is the Crus- 
galli, to which the so-called Cockspur Thorns belong. Individuals of 
this group do not form as large colonies as those of some of the other 
groups, but they are generally distributed from the valley of the Saint 
Lawrence River in the Province of Quebec to the shores of the Gulf 
of Mexico in western Florida and westward to Iowa, eastern Kansas 
and Oklahoma, and to western Texas. The species are most abundant 
in southern Missouri, Arkansas and western Louisiana. The Punctatae, 
of which the type is Crataegus punctata, one of the largest of the 
American species, is northeastern but ranges southward on the high 
Appalachian Mountains to northern Georgia, and to Missouri and Ar- 
kansas where it has a number of representatives. Species of the Vir- 
ides grow on the coastal plain of the south Atlantic states and in the 
coast region of the Gulf States to western Texas; they are most abun- 
dant in Texas, western Louisiana, southern Arkansas and in the valley 
of the Mississippi River as far north as Illinois. East of the Mississ- 
ippi River individuals of this group are not numerous, but westward, 
especially in eastern Texas, they cover great tracts of low ground; and 
the type of the group, Crataegus viridis, is under favorable condi- 
tions the most gregarious of all the American Hawthorns. This group 
is well represented in the Arboretum by C. nitida, a large tree of the 
bottom-lands of the Mississippi River in Illinois and one of the hand- 
somest of all Hawthorns. The Pruinosae is a northern group but 
ranges southward on the Appalachian Mountains, and reaches Missouri 
where it is abundant with numerous species in the southern part of the 
state and northern Arkansas. The Tenuifoliae is a distinctly north- 
eastern group but is largely represented on the Appalachian Mountains 
as far south as North Carolina, with a single species in southern Ar- 
kansas. The Coccineae is composed of large trees with large leaves 
and flowers, and large and showy scarlet fruit; it is entirely northeast- 
ern and most abundant in western New York, southern Ontario and 
northeastern Illinois. The Dilatatae is another group with large leaves, 
flowers and fruits and is confined to the northeastern states, and to 
Missouri and eastern Kansas. It is well represented in the Arboretum 
by Crataegus coccinioides, now one of the handsomest trees of the 
collection. The Rotundifoliae are entirely northeastern, and one of the 
species, C. rotundifolia, is the most northern in its range of the 
American Hawthorns. Species of this group are not found south of 
