196 M. B. WELCH AND A. R. PENFOLD. 



TWO PINNATE LEAF BORONIAS AND THEIR 



ESSENTIAL OILS, 



With Description of a New Species. 



Botany by M. B. WELCH, B.Sc, A.I.C., Economic Botanist; 



Chemistry by A. R. PENFOLD, F.C.S., Economic Chemist, 



Technological Museum, Sydney. 



[With Plates XII - XIV.] 



[Read before the Royal Society of N. S. Wales, November 2, 1921. J 



Over twelve months ago the authors decided to undertake 

 an investigation of the Boronias (N.O. Rutacese) and their 

 essential oils, and this contribution is a result of the 

 study of two pinnate leaf species. In the genus Boronia, 

 series Pinnatae, only three species are fully described for 

 Eastern Australia by Bentham in the Flora Australiensis* 

 namely, B. micropliylla Sieber; B. pinnata Smith; both 

 occurring in New South Wales, and also B. pilosa Labill., 

 from the southern States. Four other Boronias of this 

 series are limited to Western Australia. Under B. pinnata 

 Bentham synonymises B. fioribunda Sieber, but the latter 

 species has since been raised by more recent writers to 

 specific rank, chiefly on account of its large capitate stigma, 

 and in the field these two species are readily distinguished. 

 Under B. pinnata var. Gunnii, Bentham I.e. places B. 

 Gunnii of Hooker in the Flora Tasmaniae, a pinnate leaf 

 Boronia from Tasmania, with more crowded leaflets, and 

 less hairy staminal filaments than B. pinnata. Hooker (I.e.) 

 also describes B, citriodora Gunn. MSs. a species found in 

 alpine situations in Tasmania, but more dwarfed and with 

 more coriaceous leaflets than B. Gunnii. B. citriodora 

 possesses a distinct lemon scent, which is quite wanting in 



