— 93 — 



plants being infected by a "rust" fungus, Puccinia Menthce, Pers. which was 

 also observed in other districts of Germany during the summer. The fungus 

 does not appear to have affected the quality of the oil, but that such an 

 effect would be possible was shown by a private communication to 

 Prof. Thorns by Dr. Sonder, who has for many years carried on peppermint- 

 growing at Bad Oldesloe, Germany. No fewer than 4000 of Dr. Sonder's 

 slips had been attacked by Puccinia Menthce to such an extent that the 

 plants could not be gathered, as they were discoloured and had acquired 

 an almost repulsive odour, resembling that of Mentha crispa. Singularly 

 enough, Mentha aquatica, although growing in considerable quantities in 

 the same neighbourhood, had not been attacked by the fungus. 



Along with the slips, Prof. Thorns had received from his Japanese 

 grower a sample of oil distilled by the latter. The properties of this oil 

 as compared with those of the oil grown at Dahlem by Prof. Thorns are 

 given in the table below: — 



|o n o np , P on Dahlem Oil 



Japanese Uil (first and second crop) 



Spec, gravity d 21 o 0,8998 d 23 o 0,8976 



« D21 o —36,75° —31,85° 



Acid value 4,42 2,28 



Ester value 22,4 16,2 



Ester v. after acet. 263,5 264 to 265 



Cong. pt. + 10 to + 10,5° + 8° 



Ester-menthol 6,23 °/o 4,5°/o 



Total menthol 73 °/o 73,4 to 73,7 °/o 



Free menthol 66,7 °/o 68,9 to 69 °/o 



Perilla Oil. The aldehyde from the oil of Perilla nankinensis, Decne., 

 described in our previous Report 1 ), has since then been more closely examined 

 by Semmler and Zaar 2 ), to whom we supplied the oil, and who have found 

 it to be a dihydrocuminic aldehyde Ci Hi 4 O. The constants found by the 

 authors are as follow: b. p. 104 to 105° (10 mm.), di 8 o 0,9617, [« D ] — 146° 

 n D 1,50746, mol. refr. found 46,40, calc. for Ci Hi 4 0/J 45,52. The semi- 

 carbazone melts between 199 and 200° (from alcohol). 



By reducing perillic aldehyde with zinc dust in acetic acid the corre- 

 sponding perillic alcohol CioHi 6 was obtained: b. p. 119 to 121° (11 mm.), 

 d 20 o 0,9640, [«] D —68,5°, n D 1,49964. The ethyl ester boils at 123 to 126° 

 (13 mm.): d 20 o 0,9785, [«] D — 48°, n D 1,48142. The chloride of perillic alcohol 

 has the following properties: b. p. 99 to 101 ° (12mm.), d 20 o 0,9861, [a] D — 60°, 

 n D 1,49728. Reduction of the chloride with sodium and alcohol gave rise 

 to limonene ([«] D —51,5°; m. p. of the tetrabromide 104 to 105°). When 

 the perillic aldoxime is boiled with acetic anhydride and sodium acetate 



*) Report October 1910, 146. 

 2 ) Berl. Berichte 44 (1911), 52. 



