THE HI BBEU ON THE NICHARE 187 



While I was laid up Longacre made excursions in 

 different directions, so as to determine whether the 

 rubber-producing trees existed in abundance in the 

 locality. He also carried on a regular system of tap- 

 ping, obtaining samples of rubber and herbarium 

 specimens of the tree producing it. I gathered from 

 him on our return to La Prision, for I was too ill to 

 think of or discuss any subject while we were on the 

 Nichare, that the rubber- trees exist in numbers, especially 

 in the low-lying lands, which would appear to be partially 

 flooded at certain seasons of the year, but that the yield 

 of milk per tree was disappointing. What surprised both 

 of us was, that although in his experiments he had 

 obtained as I have said but a poor result, yet he daily 

 met with proofs that the trees must at times produce 

 ever so much more latex than when he carried on his 

 operations. Large flakes of coagulated milk were 

 observed where accidental injuries had happened to 

 some of the trees. In the Amazon region it does not 

 pay to tap the trees except at a certain season ; it is 

 probable that the same conditions exist on the Nichare^ 

 but it is unlikely that the seasons coincide. That is a 

 matter to be settled, so far as the Nichare is concerned, 

 by a series of experiments extending over the greater 

 part of the year. Regarding the tree producing the 

 rubber Dr. L. Britton says : 



' Referring to the samples of rubber gum, and the 

 accompanying specimens of the foliage and flowers of the 

 tree which you described to me as producing them, I 

 would say that I am informed by Dr. John K. Small, 

 Curator of the Herbarium of Columbia University, that 

 the tree is a species of the genus Micrandra, natural 

 family, Euphorbiacese, closely related to the genus 



