TUE GENUS EUCALYPTUS. 243 



In the form angustifolia, the flowers are very small, and bear a 

 great resemblance to those of E. licolor or the " Bastard Box." 

 The operculum, in some varieties, is obtuse and hemispherical, and 

 in others, conical, but the seed-vessel is uniformly of the same 

 shape, though differing in size. 



(4.) E. siderophloia is the "Bed," or " large leaved Iron Bark," 

 formerly called E. resinifera, because it yields the brown gum, or 

 Botany Bay Kino, which is the inspissated juice of the tree. The 

 wood of this species, though not so tough as that of the preced- 

 ing species, is considered one of the strongest and most durable 

 timbers of the colony. According to Sir William Macarthur, 

 there are two distinct varieties of E. sideropldoia, one of them 

 being distinguished by its "very rough bark, in broad, deep, 

 longitudinal furrows, its very broad leaves, its smooth bark on the 

 young branches, and the different grain of the wood." Both of 

 them vary from 80 to 120 feet in height, and from 24 to 48 inches 

 in circumference. The specific name is rather unfortunate, as it is 

 applicable to almost all the " Iron Barks." In a dried specimen, 

 it is difficult to distinguish this species from the "Red Mahogany" 

 and the " Leather Jacket," as all three of them have the oper- 

 culum longer than other species, and there is a similarity in the 

 shape of the seed-vessels. They are, however, easily distinguished 

 by the bark. The wood of E. sideropJiloia is of a darker colour 

 than that of E. paniculate, and the leaves are uniformly larger. 



(5.) E. melanopliloia is the "Silver-leaved" or "Broad-leaved 

 Iron Bark" of the northern parts of this colony. It occurs on 

 Liverpool plains, on the Dawson, Gilbert, and Burnett rivers &c. 

 This is a much smaller tree than any of the other Iron Barks, 

 and is readily distinguished by its sessile, opposite leaves, which 

 are glaucous or mealy white. Mr Bentham regards this as being 

 very nearly allied to E. crebra, of which he supposes it may prove 

 an opposite leaved variety. Although there is some similarity 

 in the trees, they differ not only in foliage but in habit, and 

 whilst the wood of the one is highly esteemed, that of the other 

 is not valued by practical men. Sir T. Mitchell noticed this 

 " Iron Bark" growing on the Narrau, and supposed it to be 

 allied to E. pulvigera, or the " Argyle Apple," and it is not a little 

 remarkable, that Mr. Beutham mentions its resemblance to E 

 cina'ea, a species which Dr. E. Mueller associates with the same. 



