NATURAL ORDERS. 127 



distinct, not only in the structure of its ovarium 

 and seeds, but in its leaves being altogether destitute of 

 glands, which are not only numerous in Samydese, but con- 

 sisting of a mixture of round and hnear pellucid dots, 

 distinguish them from all the other families^ with which 

 there is any probability of their being confounded. 



Sir James Smith^ has lately suggested the near affinity 

 of Aqviilaria to Euphorbiacese. But I confess it appears 

 to me at least as distinct from that order as from Samydese ; 

 and I am inclined to think, paradoxical as it may seem, 

 that it would be less difficult to prove its affinity to Thy- 

 melese than to either of them ; a point, however, which, 

 requiring considerable details, I do not mean to attempt in 

 the present essay. 



Of EUPHORBIACEiE there are twenty species in the 

 collection, or one twenty-eighth part of its Phaenogamous 

 plants. This is somewhat greater than the intratropical 

 proportion of the order as stated by Baron Humboldt, but 

 rather smaller than that of India or of the northern parts 

 of New Holland. 



The most remarkable plants of Euphorbiaceae in the 

 Congo herbarium are : a new species of the American 

 genus Alchornea ; a plant differing from jEgopricon, a 

 genus also belonging to America, chiefly in its capsular 

 fruit ; two new species of Bridelia, which has hitherto been 

 observed only in India ; and an unpublished genus that T 

 have formerly alluded to,^ as in some degree explaining 

 the real structure of Euphorbia, and from the considera- 

 tion of which also it seems probable that what was form- 

 erly described as the hermaphrodite flower of that genus, 

 is in reality a compound fasciculus of flowers.* From the 

 same species of this unpublished genus a substance resem- 

 bling caoutchouc is said to be obtained at Sierra Leone. 



' The only other genus in which I have observed an analogous variety of 

 form in the glands of the leaves, is Myroxyhn (to which both Myrospermum 

 and Toluifera belong), in all of whose species this character is very remarkable, 

 the pellucid lines bemg much longer than in SamydeK. ^ 



^ Linn. Soc. Transact. 11, p. 230. ' Vlinden's Voy. 2, p. 557. {Ante,p. 29.) 



' Linn. Soc. Transact. 12, p. 99. 



