What is a Mexican and Central American tree (Castilloa elastica and C. Markhamiana) related to the breadfruit tree. Its milky juice contains caoutchouc. Called also ule tree called?

ule — A Mexican and Central American tree (Castilloa elastica and C. Markhamiana) related to the breadfruit tree. Its milky juice contains caoutchouc. Called also ule tree. (Webster's 1913.)

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