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aration of the group for Britton and Shafer’s Trees of North 
America. In this work I was handicapped by lack of southern 
and western material, for the only species I could take up were 
those represented in our herbarium, and therefore the work is 
lacking in southern and western species 
In 1907, I wrote up Crataegus for the new Gray’s Manual, 
In this work I was still bothered by lack of knowledge of the 
southern and western forms; while Dr. Sargent has since pub- 
lished over two hundred species, from the northeastern range. 
I was aided, however, by easy access to the Arnold Arboretum 
herbarium, and IJ had an excellent opportunity to observe the 
many living forms then coming on in the Arboretum. 
In November, 1907, I had my first trip South, visiting White 
Sulphur Springs, West Virginia; Biltmore, Fayetteville and 
Raleigh, North Carolina; and getting much valuable fruiting 
material. At this time I spent three days in Ashe’s herbarium, 
and three months at Biltmore; and took North with me all of 
Beadle’s species and most of Ashe’s species which I did not 
already have. 
In 1903 and 1904, Mr. C. L. Boynton, of the Biltmore Her- 
barium, made extensive trips in North Carolina, visiting Ashe’s 
type stations; and he also covered a good deal of Kentucky, 
West Virginia and Virginia. Those explorations helped to settle 
some of our vexing problems and also made others. 
In August, 1908, I started on another southern trip. Most 
of the species and groups of the South, except in the mountains, 
are different from the northern plants; and one problem to be 
settled was, How many of the southern species reach southern 
Virginia, West Virginia and Kentucky. Another problem was, 
How many of the northern species extend south in the mountains. 
This journey gave me much information along these lines. 
I first stopped in southwest Virginia, visiting Finchley, Law- 
renceville, Emporia and Franklin, along the southern border. 
is trip showed me that we cannot expect many of the southern 
species in Virginia. Of the great group Flavae, C. flava Aiton 
was the only one seen, and of the southern /z/ricatae, perhaps 
one species. I reached Fayetteville, North Carolina, in time to 
