220 



HYDROCYANIC ACID IN PLANTS. 



PAKTi.-ITS DISTRIBUTION IN THE AUSTRALIAN 



FLORA. 



By Jamks M. Petrik, D.Sc, F.I.C, Linnran Macleay Fellow 

 OF THE Society in Biochemistry. 



{Front tlic I'fi ijftloUxjicdl Lahonitori/ of the U niverslty of 



Sydney.) 



It is now more than a century since Boehm, the Berlin 

 apothecary, obtained hydrocyanic acid by distilling the water 

 in which bitter almonds had been steeped. This was the first 

 discovery of the formation of hydrocyanic acid by plants. 

 Since that time this acid had been detected in a number of 

 well-characterised plants, such as the cherry-laurel, rubber- 

 tree, and cassava, hut up to the end of last century the list of 

 svich plants was very small. At this period, theoretical specu- 

 lations on the role of hydrocyanic acid in metabolism created 

 a new and wider interest in the subject, and resulted in the 

 initiation of two separate lines of research: — (1) The bio- 

 chemical problems connected with the origin and fate of hydro- 

 cyanic acid in plants, and (2) the detection of this substance, 

 in order to determine its occurrence and distribution through- 

 out the vegetable kingdom. 



The first systematic examination for hydrocyanic acid in 

 plants was begun by Greshoff, in the Botanic Gardens of 

 Buitenzorg, and later, at Kew. lie published, in 1906, a 

 complete list of all the known cyanogenetic plants, and a fur- 

 ther supplement, prior to his death, in 1909. 



In this list are included only four plants native to Aus- 

 tralia. The present investigation may therefore be considered 

 as a continuation of similar work on the indigenoiis flora of 

 Australia. The majority of the plants have been collected by 

 me personally, in the bush. A number were obtained from 



