Ohara : On the Micilage ok Hydkancea Paniculata, Sieb. 



129 



cellular cavities formed by the surrounding cells. So the crystal-containing cell 

 assumes, in the cross section of the stem, a polygonal shape. 



As the cr)-stals in the cell take the form of Raphides, each cell elongates in 

 one direction ; and, when found in the stem, it lies parallel to the long axis. 

 Accoriiing to HOLLE's-'' statement, these raphides-containing cells occur 

 throughout the tribe Hydrangae and are regarded as one of the characteristics 

 of this tribe. Raphides are enclosed by a thick, homogeneous, sometimes brown- 

 coloured, transparent mucilage. SAWAMURA ^' once analyzed the mucilage 

 and recognized in its hydrolizetl products galactose and arabinose. J^y my ex- 

 periment, it shows microchemically the following reactions : 



1). With Delatield's haematoxylin, with safranin and methylen blue more 

 easily it can be stained. 



2). With ruthenium red it is stained intensely red. 



3). By the following reagents no reactions can be obtained; (a) Iodine 

 solution, (b) Zinc chloride iodine, (c) Iodine and sulphuric acid, (d) 

 Congo red. (e) Phloroglucin and h)'drochloric acid. ( f) Millon's 

 reagent. 



4). By the lead subacetate white precipitates can be obtained. 



5). By the ammonium copper o.xide solution it can not be dissolved. 



6). In the water first it swells and then totally disappears, a proof of complete 

 dissoluiion. 



And the extract of the thin slices of the bast got by boiling them in water 

 can be precipitated by adding some strong alcohol. After boiling the extract in 

 diluted li_\-drochloric acid, it reduces the Fehlings solution, although the extract 

 shows no reaction whatever before its treatment with the acid. By the reactions 

 above stated it can be concluded that the mucilage belongs to the pectin com- 

 pounds. 



From the economical point of view, it is not unnecessary here to describe 

 ln)W the raphides-containing cells are distributed in a plant body, so that those 

 who are interested in the matter may tell what part of the plant is most richly 

 endowed with the mucilage. The following results obtained by my observation 

 may serve as a suggestion to this point :— 



2) Holle; Beiträge zur Anatomie der Saxifragaceen und deren Systematik. Botanisches Central- 

 lilalt. 1S93. 



3) Savvamhka ; in tlie Manufacture of Japanese paper' by YoSHIi. (In Japanese) 1S97. 



