The Garden Magazine, April, 1921 
103 
from seed, and the progeny do not show any diverse varietal 
tendency, which is always seen in recent hybrids. The Dar- 
winian explanation of the origin of species probably applies. 
The geographical distribution of the groups is of much inter- 
est. The Crus-galli, Punctatae, and Molles groups are widely 
distributed from the valley of the St. Lawrence River to Texas. 
The Tomentosae group, which is recognized by the longitu- 
dinal cavities on the inside of the nutlets, is mainly a northern 
group, but it extends in a few species to the Rocky Mountains 
and the northern Pacific states. Species of this group are a 
conspicuous feature of the vegetation in central and northern 
Ontario, Canada, and particularly abundant at Belleville and 
Kingston, Ontario. 
The Anomalae group has some general features in common 
with the Tomentosae, with 
very slight indentations on 
the inner faces of the nutlets, 
but this group is mostly con- 
fined to Ontario, Michigan, 
New York, and Pennsylvania. 
The Rotundifoliae group is 
very common along the val- 
ley of the St. Lawrence River. 
The species are mostly north- 
ern, but there are represen- 
tatives in Virginia, North 
Carolina, Tennessee, and 
Georgia, and westward in 
Colorado. 
The Pruinosae group is 
mostly northern and is repre- 
sented by numerous species 
in Western New York, Penn- 
sylvania, and New England, 
but it does extend beyond the 
Mississippi. 
The Medioximae group, 
which in many respects is 
similar in group characters 
to the Pruinosae but distin- 
guished by a sessile calyx, 
has about the same distribu- 
tion as the Pruinosae. 
The Tenuifoliae group is 
represented by a large num- 
ber of species in the north- 
eastern states, and does not 
occur in the southern states 
except at high altitudes. 
The Intricatae group is 
found sparingly in Ontario, a 
number in New York State, 
and in New England, and 
they extend southward to 
Tennessee, Alabama, Georgia 
and Florida. The species are 
most abundant in Pennsyl- 
vania where thirty-three oc- 
cur. The individuals in this 
group are beautiful garden 
plants. 
The Bracteatae, Triflorae, 
Aestivales and Microcarpae 
groups are exclusively con- 
fined to the southern states. 
The Washington Thorn, 
Crataegus cordata, which is 
extensively planted in the 
north, is of the Microcarpae 
group. 
The Flavae group is onl> 
found in the south-eastern states; and the Virides group in the 
South Atlantic and Gulf states, and the valley of the Missis- 
sippi contains some beautiful and highly ornamental species. 
Many of these Hawthorns are revealing themselves as excel- 
lent garden plants, so that it is really a difficult matter to select 
twelve, eighteen, or twenty-four; but, nevertheless, by rigid 
selection of typical species in each group I am able to make this 
list of twenty-two which seem to me to be most desirable, taking 
garden use only into consideration. 
Crus-galli Group. There are two very important species. 
Crataegus fecunda forms a tree twenty to twenty-five feet, with 
stout, wide-spreading branches making a broad, round-topped 
open head. The usually oval leaves are deep green and lustrous. 
The clusters of small flowers, with ten to fifteen stamens and 
ONE OF THE TOMENTOSAE GROUP 
Crataegus macrantha is an example of the group widely distributed in the North Eastern region. It has broad hairy 
leaves and grows up to 15 feet. The white flowers of May are followed by clusters of scarlet fruits in September 
