2 BULLETIN 119, U. S. DEPARTMENT OF AGRICULTURE. 
and by Bentham (1840, p. 139) in the subgenus Strophostyles. 
Strophostyles Elliott is based on the American plant called Phaseolus 
umbellatus by Muhlenberg. American botanists generally consider 
Strophostyles a valid genus, differing from Phaseolus in having the 
keel curved but not spiral. The two keel petals are inflated near 
the middle in the broadest part and each has a semicircular expansion 
on the dorsal edge. The stigma is terminal; that is, there is no 
appendage at the tip as in Phaseolus. The pods and seeds of Stroph- 
ostyles are much like those of the mung and related species, and 
it was apparently on these characters that Bentham associated the 
two. The keel and stigma characters of Strophostyles, however, 
indicate that there is no such close relationship. 
The five species possess the following characters in common: 
Plants annual; stipules with a basal appendage; flowers yellow; 
keel spirally coiled, bearing on one side a hornlike appendage; style 
hairy, prolonged into a narrow appendage beyond the stigma; 
stigma lateral, subterminal; pods linear, subterete, sometimes toru- 
lose; seeds globose to oblong; hilum narrow, linear. The style 
and stigma characters of the adsuki are like those of the kidney bean 
(Phaseolus vulgaris) in that the terminal appendage is flattened, 
while in the other four species it is terete. This difference is appar- 
ently not significant, except as showing that these species truly belong 
with Phaseolus. The other characters, however, seem sufficient to 
warrant the recognition of a subgenus for the mung and its allies, 
- which may be called Ceratotropis, from the Greek words signifying 
horn and keel. 
The mung bean is cultivated more or less extensively in all parts 
of Asia where it will mature and also in southeast Africa, where it 
was probably carried by Hindoo traders. The urd and the moth 
bean are cultivated only in India. The adsuki is confined to Japan, 
Manchuria, China, and Chosen (Korea), unless a similar bean in Nepal 
and Sikkim is identical. The rice bean is most frequently seen in 
China and India, but it is also cultivated in Japan and the Philippines. 
Presumably the cultivation of all of these was relatively more 
important previous to the discovery of America, which led to the 
general dissemination of the kidney bean and the Lima bean, both 
of which are now largely cultivated in all the regions mentioned. 
Nevertheless, the five oriental species are still of considerable agri- 
cultural importance and doubtless will always be cultivated. All 
of them have been rather extensively tested from the standpoint 
of forage and of green-manure crops in the United States, especially 
during the past six years, but it seems doubtful whether any of 
them can compete in these respects with the cowpea and the soy 
bean. As producers of seed for both human food and animal food, 
however, there are possibilities in these crops well worthy of much 
further investigation. Their final position in American agriculture 
