236 BOTANICAL MICROTECHNIQUE. 



Schwarz has been used elsewhere in the literature, at least 

 the names of his eight compounds may be given here. 



Two of them occur in the chlorophyll granules, chloro- 

 plastin and metaxin. The first of these represents the green 

 fibrillae within the chloroplasts, and between them is the 

 -water-soluble metaxin. 



In the nucleus Schwarz distinguished five substances, 

 -amphipyrenin, which forms the nuclear membrane ; pyrenin, 

 the substance of the nucleoli ; chromatin, the strongly stain- 

 ing material of the nuclear framework ; and linin and para- 

 linin, the former of which forms a fibrillar network in the 

 nucleus, while the latter fills the meshes of this net. 



In the cytoplasm Schwarz finds only one proteid, which 

 lie calls cytoplastin. 



13. Ferments. 



240. It was stated by Wiesner (IV) that pepsin, diastase, 

 and the gum-ferment described by him give characteristic 

 color-reactions with orcin and hydrochloric acid, which are 

 rnicrochemically applicable. But Reinitzer (II) showed that 

 these reactions occur with various carbohydrates, and most 

 probably depend upon the fact that the reagent splits off 

 from them furfurol or related compounds. 



But Guignard has recently tried to determine the location 

 of emulsin and myrosin, partly by the use of orcin. 



a. Emulsin. 



240a. Emulsin splits the glucoside amygdalin, contained 

 in bitter almonds, into prussic acid, oil of bitter almond?, 

 and sugar. It occurs, according to Guignard (III), in the 

 leaves of Prunus Lauro-cerasus, exclusively in a parenchyma- 

 tous sheath surrounding the vascular bundles. This author 

 Teaches this conclusion from the fact that only these cells 

 'form prussic acid with a solution of amygdalin ; while the 

 spongy and palisade parenchyma, which, on the other hand, 

 forms prussic acid with a solution of emulsin, is plainly to 

 foe regarded as the seat of amygdalin. 



