138 THE CEARA RUBBER TREE 



undergoing trial in several countries for comparison with 

 M. Glaziovii. 



In the following account the Ceara tree {M. Glaziovii) 

 is fu-st dealt with, and then a short description is given 

 of the new species. 



Botanical Characters. — The Ceara rubber tree was first 

 described in 1874 by J. Miiller, who named it Manikot 

 Glaziovii after its discoverer, Dr. Glasiou, a French 

 botanist. It belongs, like the Para tree, to the natural 

 order Euphorbiaceae, and is a moderate-sized tree 30 

 to 50 ft. high with an erect stem 8 to 20 in. in diameter. 

 As a rule the branches are numerous and spreading, 

 forming a dense, rounded crown, but in some trees only 

 a few erect branches are developed. The bark is thin, 

 purple-grey, and the outer silvery layers can be readily 

 stripped off. The leaves are palmate, the lobes being 

 deeply cut and varying in number from three to nine m 

 leaves on the same tree ; they are of thm texture, smooth 

 on both surfaces, chirk bluish-green above and paler 

 beneath. The flowers, which are rather large, are uni- 

 sexual and both male and female occur in the same 

 raceme. The fruit is a three-celled capsule, each cell 

 containing a single seed ; it is nearly globular, and when 

 ripe is hard and dry, splitting to release the seeds. The 

 latter are plano-convex in shape and have a thick, hard 

 seed-coat, the outer layer of which is smooth and shiny, 

 varying in colour from grey to dark brown and mottled 

 with purplish-black patches. (See Plate V.) 



Distribution. — In Brazil Manihot Glaziovii is most 

 abundant in the States of Ceara, Piauhy, and Bahia, 

 Cross, who visited the State of Ceara in 1876 in the course 

 of his journey through South America for the purpose of 

 collecting rubber seeds and plants for the Government 

 of India, found the tree growing freely in the flat country 

 lying between the town of Ceara on the coast and the 

 mountains, where the elevation was not more than 200 ft. 

 The climate of this region is very dry and arid for a con- 

 siderable portion of the year, and many of the crops can 

 only be grown by irrigation. The rainy season extends 

 from November to May or June, but it is stated that 

 in some years very little rain falls.^ The daily temperature 

 recorded on the coast ranged from 82° to 85° F., but 

 Cross considered that in the ulterior it was often 90° F. 



