142 A. R. PENFOLD. 



OH 3 



I 



o 



H 2 / \ OH 



H 2 x 00 



\/ 



OH 



I 

 OH 



/ \ ' 

 H 3 0H 3 



It is therefore, identical with the following:— 



(1) ZV-Menthenone-3 prepared synthetically by Wallach. 1 



(2) The ketone found occurring in Japanese Peppermint 



Oil, 2 identical with (1). 



(3) The ketone found in Oamplior Oil, identical with (I). 3 



(4) A -Menthenone-3 found in the oil of Cymbopogon 



seminar ens is. 4 



The name piperitone takes priority for this ketone, 

 A'-Menthenone-3, as it was first discovered by H. G. Smith, 

 F.c.s., in Eucalyptus oils in the year 1900. 5 



I have to express my thanks to Mr. T. O. Roughley, 

 Economic Zoologist, for the photograph of the crystals of 

 diosphenol, and to Mr. F. Morrison, Assistant Ohemist, for 

 his help in this work. 



1 Ann. 362 (1908), p. 271. 



a Schimniel & Co., Semi-annual Report, Oct. 1910, p. 97. 



3 Gildemeister & Hoffmann, 2nd German edition, p. 432. 



4 Roberts, J. C. S., 107 (1915), 1465. 



5 This Journal, Vol. xxxiv, (1900), p. 136. 



