BY M. B. WELCH. 



435 



glands were searcely evideut within a distance of 8 mm. from the cambium. 

 Towards the outside tlie loose thin-walled areas become disintegi-ated, leaving the 

 more persistent fibre zones and hence producing the decided bark corrugations. 

 Plate xlix., fig. 11 shows a transverse section of the mature bark of E. Smithii, 

 about 15 mm. from the cambium. The oil-glands are cliaracteristically prominent. 

 Crossing the field obliquely are seen numerous narrow medullary rays and usual- 

 ly at right angles to these are the bands of thin-walled, loosely-arranged paren- 

 chymatous tissue in which the oil-glands occur. The fibre groups are irregularly 

 arranged and, although to some extent intermingled with the gland-bearing 

 tissue, the great majority form distinct areas, readily visible with the naked eye, 

 in which glands do not occur. Tangentiallj^ it is possible to obtain large sections 

 in which there is no trace of the usual elements of the phloem, the entire field 

 being composed of the loose parenehjnna and numerous oil-glands. In radial 

 section (PI. xlix., fig. 12) two narrow fibre zones have been cut, between which 

 is a broad gland-bearing area typical of the species. The contents of the oil- 

 glands in the outer .portion are dark in colour and practically insoluble, whereas 

 towards the cambium the contents are light yellow and soluble in 90 — 95% 

 alcohol. 



E. nova-anglica Deane & Maiden. "Black Peppermint." 



Bark straight, semi-persistent on the trunk, ribbony on the branches. Oil- 

 glands were not numerous in the material examined, e.g., in one area of 32 sq. 

 mm. only one oil-gland was found. The contents were bright yellow and as a 

 rule slowly soluble in 100% alcoliol. Distinct secondary glands were found in a 

 twig of herbarium material. 



E. pulverulenta Sims. 



A shrub with thin weak stems, possessing a smooth bark, tending to flake 

 off. In section the arrangement of the fibres is very regular. Oil-glands of a 

 secondary nature were' found in stems 7 mm. in diameter, but are not numerous 

 in this species; sections often failed to show very definite evidence of their 

 presence. 



E. nibida Deane & Maiden. "Candle Bark." 



A tree with a smooth white bark, falling off in ribbons. Oil-glands very few 

 in the material examined and small (averaging about 0.06 mm. in diameter). 

 Contents ranging from bright yellow and pale lemon-yellow in colour, almost 

 soluble in 100% alcohol. The bast fibre zones are very regularly arranged in 

 rows parallel to the cambium, evidently accounting for the regiilai' clean stripping 

 of the shed bark and the smoothness of that left behind. 



E. Stuartiana P.v.M. "Apple of Victoria." 



Possesses a fibrous bark, which "would allow this species to pass almost as a 

 Stringybark" (Mueller, 1879-84). Oil-glands are comparatively few in number, 

 measuring up to 0.15 mm. x 0.10 mm. The bark was not fresh and the contents 

 of the inner glands were represented by a dark cellular fringe. This became 

 lighter in colour and went into solution readily in 100% alcohol, leaving only a 

 small insoluble residue. Small twig-s of herbarium material showed undoubted 

 secondary glands, contents partially filling the cavity. Fresh material also 

 showed glands with light-coloured contents. There is a tendency to form stone- 

 cells, irregular in outline. 



