24 
ence of longitudinal cavities on the inner faces of the nutlets of the 
fruit. The Molles, which is most closely related to the Coccineae, is 
mentioned last that attention may be drav/n to some of the species which 
are already in flower. The distribution of this Group is peculiar. It 
is represented in the valley of the St. Lawrence River in the Province 
of Quebec, in Maine, eastern Massachusetts and northern Delaware; 
from western Vermont and Massachusetts and from western Pennsyl- 
vania it is common westward to eastern Nebraska and Kansas; it oc- 
curs in middle Tennessee, northeastern and eastern Mississippi and in 
northern Alabama where there is a single species. It is largely repre- 
sented in Missouri; there are several species in Arkansas where they 
are m.ost abundant in the valley of the Red River; in eastern Texas 
several species are widely distributed, abounding in the valley of the 
lower Brazos River and extending westward to that of the San Antonio. 
The Group has no representative in Louisiana, only two in Mississippi 
and one in Alabama; in the rest of the country, so far as is now known, 
the Group is not represented. The largest trees are found in this 
group; they have large leaves more or less covered with hairs, especi- 
ally early in the season, large flowers in many-flowered clusters, and 
large, scarlet or rarely yellow, usually dry and mealy, often ed- 
ible fruit. The Group is North American with the exception of Cra- 
taegus peregrina, a plant raised many years ago at the Arboretum 
from seeds - received from the Botanic Garden at Petrograd. This 
handsome tree has large, dark purple fruit unlike in color that of any 
American species. Its native country is still unknown, but it has been 
suggested that it might have come originally from Persia or central 
Asia. Several trees of C. peregrina are now in full bloom in the Ar- 
boretum. Several other species of this Group are now covered with 
flowers. Large trees of C. arnoldiana, C. urkunsana and C. submol- 
lis deserve attention. The first was discovered many years ago grow- 
ing wild in the Arboretum, and although now commonly cultivated is 
known as a wild plant only in a few isolated stations. The large scar- 
let fruit, which ripens at the end of August or early in September, 
makes this the handsomest of the Thorns in late summer. C. submolLis 
is another species which was first noticed growing in the neighborhood 
of the Arboretum but is now known to grow in Maine and the Prov- 
ince of Quebec. The pear-shaped fruit ripens four or five weeks later 
than that of C. arnoldiana. The scarlet fruit of C. arkansana is still 
brilliant on the branches in November. There are many other species 
of the Mollis Group now in flower, and different Hawthorns will be 
opening their flower-buds here during the next five or six weeks. 
The Arboretum is a good place in which to study Hawthorns. Most of 
the Old World species and varieties are established, and some three 
hundred and fifty American species now flower and ripen their fruit here 
every year. For those parts of the country in which the soil is im- 
pregnated with lime and the winter climate severe, no other genus can 
furnish such a variety of trees and shrubs with handsome and conspic- 
uous flowers and fruit. 
