106 R. T. BAKER AND H. G. SMITH. 



those under this measurement. In such a classification, 

 this plant falls into the first group, in which are found P. 

 lasianthos, P. prunelloides, P. coerulea, P. melissifolia. 



From P. lasianthos it differs in the absence of serrations 

 in the leaf, in the calyx, corolla and in other appendages. 



From P. prunelloides and P. coerulea in the stripe, colour, 

 size of leaves, altogether apart from any inflorescence 

 distinctions, and for the matter of that, P. ovalifolia as 

 well. 



P. melissifolia has a distinct foliage and flower from 

 this species. Systematically it might be placed between 

 P. ovalifolia, from which species however it differs in 

 shape and size of leaf, and inflorescence, and P. discolor, 

 R. T. B., in shape of leaf. Its leaves are quite distinct in 

 shape from any species known to us. It has no affinity 

 with the species P. granitica and P. teretifolia recently 

 described by Maiden and Betche, Proc. Linn. Soc, Vols, for 

 1905 and 1908 respectively. 



Essential Oil. 

 The material for distillation was collected in March 

 1912. It was quite green when received, and consisted 

 mostly of stalks, about two feet long, with leaves attached. 

 The yield of oil was equal to 0*71 per cent., 270 lbs. of 

 leaves and branclilets giving 30J ounces of oil. The crude 

 oil was yellowish in colour when freshly distilled, but this 

 soon altered in the light, becoming considerably darker 

 after forty-eight hours; this darkening was evidently due 

 to the presence of the phenols. 



The odour was not distinctive, although that of cineol 

 was readily detected. The oil was somewhat mobile and 

 readily soluble in alcohol. When two or three drops of the 

 oil were heated with an equal weight of potash, and twenty 

 drops of chloroform, the colour reaction for carvacrol or 



