Nov. 1909.] SHIRAL— CITRUS TRIFOLIATA IN JAPAN. 199 



that old man and not protected from the extreme cold, they 

 could not have continued their life so long. 



2). I saw a plant in the garden of Mr. Kaneko in Fuku- 

 yama, Hokkaido, growing exposed to weather for more than 

 four or five years but with no visible increase in size and in 

 very bad condition. I do'nt know whether this plant is still 

 alive or not. I have sent a letter of inquir}' to the owner but 

 recieved no answer till to-day. I am sure that the plant 

 survived till the 3 r ear before last. In the same district some 

 one has planted this tree in great number and attempted to 

 make hedges, but the branches in the windy places soon 

 perished during winter and in the following three years all the 

 trees in the plantation died off. The small pot plant of the 

 trifoliate orange which was placed in the sheltered position and 

 protected from cold continued to grow without freezing even 

 in this places. 



" From the foregoing I am inclined to say that although 

 Hakodate is the mildest part in Hokkaido yet it is unfit for the 

 cultivation of the trifoliate orange, unless suitable protection is 

 given during winter season. I should think that Hakodate is 

 outside of the northern limit of distribution of this tree." 



(12) Letter from Aomori Branch Office of Forestry De- 

 partment. 



" I have heard that the plant is found in Hachinohe-mach 

 in Sannohc district, but we find this tree growing no other 

 places in Aomori-prefecturc. In Iwatc-prcfccturc it reaches to 

 [chinoseki in Nishiiwai district where it grows as dwarf 

 shrubs." 



from the above mentioned 12 letters we are enabled to 

 know the northern limit of the distribution area of this plant 

 at once and are very much obliged to those gentcmen and 

 public institutions that have favoured us with those kind 

 letters. 



