113 



3. E. mannifera Mudie. 



One species of Eucalyptus affords a substance, of which the medicinal properties have been tried 

 in Australia, and which, should it be found to suffer no injury or decomposition during the voyage, might 

 materially reduce the price of manna, which still retains its rank as a medicine. 



Until the substance itself, which appears rather difficult to preserve, be laid before the Society for 

 their examination and decision, it may not be altogether useless to offer a few notes on the plant, as even 

 that is but imperfectly known, and has not, it is believed, been figured or described in any scientific work. 

 The following are the characters, and a few points in the description : — 



Generic Character of Eucalyptus. Calyx superus, persistens. truncatus ante anthesin tectus. Operculo 

 mtegerrimo, deciduo. Corolla nulla. Capsula quadrilocularis, apice dehiscens, polysperma. 



Natural Order : Myrtaceae. 



Specific Name : Eucalyptus mannifera. (Manna gum tree.) 



Specific Character : Operculo hemisphferico acutiusculo, umbellis axillaribus terminalibusve 4-6 floris, 

 eortice albo-cinereo. 



The principal habitat of this tree is upon the elevated downs into which the Blue Mountains subside 

 and upon the adjoining slopes. It grows to the height of from thirty to forty feet, of irregular growth, 

 and having a number of slender branches. As is the case with almost all the genus, the leaves, which are 

 simple, lanceolate, and entire, are placed vertically, by a peculiar twist of the foot-stalk. 



From the accounts given of it, it does not appear that the manna produced by this Eucalyptus i* 

 very different from that yielded by the Fraxinus, on the coast of the Mediterranean ; though, as common 

 report describes it as having less of the nauseous taste, it may be less efficient as a medicine. Like the 

 manna of Europe, it is reported to contain a saccharine and a mucous ingredient, both of which are easily 

 soluble in water, and partially so likewise in the atmosphere, when moist. It obviously arises from a 

 rupture in the cortical vessels of the tree, produced not by the puncture of insects, but by atmospheric 

 action, as it is produced only in the dry season, and the quantity varies with the degree and duration of 

 the drought. 



Toward the close of a long dry season, it is found so abundant on the ground under the trees, that 

 several pounds may be collected by one person in a few minutes ; but when rain begins to fall it melts, 

 and disappears almost as rapidly as snow. 



It is worthy of remark that this substance, manna, which is reported as being so similar, as afforded 

 by the Ash of Europe and the Eucalyptus of Australia, and which has not been found, possessing the same 

 qualities, upon any other species of plant, should yet appear to be an exudation of two genera which differ 

 so much in every other respect, and are indigenous only in countries which are distant from each other by 

 nearly half the circumference of the globe ; and it deserves further notice, as being one of the few instances 

 of near coincidence in a substance where most of the productions of nature are so dissimilar. (Trans. 

 Med. Bot. Soc, 3, 24 [1834].) 



The brief Latin description has been copied from Allan Cunningham's note on 

 his herbarium specimen; the essential part of the description of the manna and its 

 occurrence is also taken by Mudie from the same source. 



Walpers' Repertorium Botanices Systematica, Vol. ii, p. 163 : — 



E. mannifera Moudie mss., in Transact, of the Med. Bot. Society, iii, 24. Foil, lanceolatis verticillatis 

 integris ; operculo hemisphserico acutiusculo ; umbellis terminalib. axillaribq. 4-6 floris ; eortice albo 

 cineraseente. Crescit in Nova Hollandia. 



Bentham (B.F1. iii, 240), in putting E. mannifera A. Cunn. under E. viminalis 

 Labill., adds "and perhaps also Moodie: Walp. Rep. ii, 163, although incorrectly 

 described." 



