JOURNAL OF AGRIffllTURAL RESEARCH 
DEPARTMENT OF AGRICULTURE 
Voiv. I Washington, D. C., October io, 1913. No. 1 
CITRUS ICHANGENSIS, A PROMISING, HARDY, NEW 
SPECIES FROM SOUTHWESTERN CHINA AND ASSAM 
By Walter T. Swingle, ' 
Physiologist in Charge of Crop Physiology and Breeding Investigations , 
Bureau of Plant Industry 
INTRODUCTION 
A study of the wild relatives of the orange begun a few years ago in the 
hope of finding new material for use in hybridization or as stocks has 
resulted in bringing to light a number of very interesting wild species, 
some of them new and many of 
them very little known. One of 
the most remarkable of these is 
a wild Citrus, native to south¬ 
western China. This species is 
cultivated in the vicinity of 
Ichang, and it bears a very large 
lemonlike fruit that is of suffi¬ 
ciently good quality to cause it 
to be shipped to markets several 
hundred miles distant. It grows 
wild farther to the north and at 
a higher altitude than any other 
species of Citrus and is undoubt¬ 
edly very hardy, which makes it 
of great promise for use in breed¬ 
ing cold-resistant citrous fruits. 
Because of its unusually large 
seeds it promises to yield very vigorous seedlings and to be, in conse¬ 
quence, a useful stock on which to graft oranges, lemons, and other 
cultivated species of the genus. 
Mr. Augustine Henry collected excellent material of this species 
around Ichang, China, from 1885 to 1888. His specimens are found in 
many herbaria under the name 11 Citrus medica L., var.” The best 
specimens, however, are those collected by Mr. E. H. Wilson, first in 
1900 to 1903 for Veitch & Sons, and again in 1907 for the Arnold 
Arboretum, this latter material comprising an abundance of flowering 
specimens, young fruits, and also ripe fruits in alcohol. 
B 
A 
Fig. i.— Citrus ichangensis , n. sp.: A t Pistil after the 
petals and 3 tamens have dropped but before the 
style has fallen off; from a para type in the herbarium 
of the Arnold Arboretum; E. H. Wilson No. 2230A; 
2i times natural size. B , Stamen as seen from one 
side; from a paratype in the herbarium of the Arnold 
Arboretum; E. H. Wilson No. 2230A; 2^ times nat¬ 
ural size. C, Two seeds deformed by mutual pres¬ 
sure; from a paratype in the National Herbarium; 
A. Henry No. 3423 (?), bottle A; natural size. 
(Drawn by J. M. Shull.) 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
(1) 
Vol. I, No. 1 
Oct. 10, 1913 
G—1 
