ON THE MUCILAGE OF HYDRANGEA 

 PANICULATA, SIEB. 



By 

 KaMETAKO ÜHAKA. 



A- m m. ± flis 



In llic niaiuifacture of Japanese paper, a kind of mucilaijc from the stem of 

 Hydranoca pauiculata, Sieb, is an indispensable substance. It is used to suspend 

 in the water the fibres of which Japanese paper is made, so as to arrange them in 

 a parallel order when the)' arc taken out in a hand frame. " 



In Hokkaido, where the plant in question grows luxuriantly, people strip the 

 stems of their bark and cut the bast into thin slices. The mucilage obtained by 

 squeezing the ncll moistened slices is mi.xed with the water in which the beaten 

 fibres has already been steeped ; by this, the mucilage serves, as already been said, 

 to suspend the fibres in the water. 



For the purpose of examining where and how the plant has nuicilage in stoi"e, 

 I collected several parts of the plant in the vicinity of Otaru, .-\ugust, 1915. I 

 had also an o; poortunity, at the end of March, 1916, to take an observation of a 

 few old stem, 5-9 cm. in diameter, sent me by a member of the Yamakoshi Factory, 

 SapiJoro. . 



On the examination of the hand section of the stem, it was found that the 

 mucilage produced from the i)lant is nothing but the contents of the crystal-con- 

 taining cells, which usually attain their full de\"elopment in the bast of the stem- 



A well-developed crystal-containing cell exceeds adjoing parenchymatous cells 

 two or three times in breadth. The thin membrance, which encloses the cell, 

 and the turgidity of the contents within make the cell expand and fill the inter- 



l) Saeki ; An opinion on the industry of Japanese paper. (In Japanese) Tlie journal of cliemical 

 industry. Tokyo. 1903. 



[Trans, of Sapporo Natural History Soc. Vol. VI. Part 2. June, 191Ö.] 



