ON CEDAR GUM (GEDRELA AUSTRALIS, F.v.M.). 



By J. H. Maiden, F.L.S., F.C.S. 



The well-known "Cedar" or "Red Cedar" of New South Wales 

 and Queensland is the produce of a Cedrela, but in regard to the 

 species there is a difference of opinion. Bentham (B.Fl. I. 387) 

 considers it to be identical with C. Toona, Roxb., the Indian Toon 

 Tree, which produces " Moulmein Cedar " and one of the " Chitta- 

 gong woods." Baron von Mueller, on the other hand, created a 

 new species for it (C. ausfralis, F.v.M.). It is very certain the 

 affinities of the two trees are very close, and it becomes interesting 

 to see if examination of any of their products tends to throw any 

 light on the subject. 



The writer is not aware that the finding of gum on the New 

 South Wales Cedar has hitherto been recorded, but a collector 

 sent to the Technological Museum a small quantity recently. 

 An old cedar-getter says that trees well exposed to the sun 

 (? in unsuitable situations) yield most gum. 



It is a very pale yellow gum, almost colourless, and in thin 

 tears about an inch long. Between the teeth it almost feels 

 leathery. It swells up largely in cold water, but in the course of 

 twenty-four hours it nearly wholly dissolves, forming a solution 

 colourless and faintly cloudy, like good gum arable, and leaving 

 a small percentage of metarabin. 



It is one of the gums which form a connecting link between the 

 Arabin group, — those gums which dissolve almost immediately in 

 water, and the Metarabin group, — those which merely swell up in 

 that liquid. It forms a fair mucilage, and on account of its 

 freedom from colour it would be a valuable commodity if obtainable 

 in any quantity. An analysis gave the following result : — 

 67 



