62 SCIENCE PROGRESS. 



two bodies in the seeds. He found the emulsin to be pre- 

 sent in both varieties of the almond, and to be chiefly 

 localised in the fibrovascular bundles. He further ascer- 

 tained that the glucoside, amygdalin, is only present in the 

 cotyledonary parenchyma of the bitter one. The absence 

 of the glucoside from the seed of the sweet almond points, 

 of course, to the conclusion that even if it be a nutritive 

 body it is not one of very great prominence in the nutrition 

 of the embryo on germination. 



Guignard has published within the past few years a 

 series of researches which deal primarily with the localisa- 

 tion of the enzymes which decompose the glucosides, but 

 which incidentally throw a certain light upon the occurrence 

 and meaning of the latter. In his first papers (64) he treats 

 of the amygdalin which is found in the almond and in the 

 cherry laurel, in the latter of which it is found to have a 

 fairly copious distribution. He confirms Johansen as to its 

 position in the seed of the almond, and still more closely 

 localises the enzyme. In the laurel (Prunus lauro-cerasus) 

 the parenchyma of the leaves as well as of the axis appears 

 to contain it in solution in the cell-sap. The occurrence of 

 the emulsin is confined to the neighbourhood of the con- 

 ducting- tissues, it being chiefly found in the endodermis 

 round the fibrovascular bundles. In the bundles of the axis 

 of the embryo in the almond the ferment occurs in the many 

 layered pericycle, chiefly outside the bast. The distribution 

 of the amygdalin is not definitely known. It may happen 

 that the fluid sap containing it may travel along the cellular 

 tissue, and the occurrence of the ferment which decomposes 

 it, in the immediate neighbourhood of the conducting tissues, 

 suggests that it is charged with the duty of preparing from 

 the glucoside certain nutritive products that may easily make 

 their way to the conducting tissues, and so travel to the 

 actual seats of constructive metabolism. That sugar so 

 travels is of course a matter of every-day experience, but 

 whether or no the remaining products are made use of in a 

 similar way is open to discussion. On the other hand it 

 may be that the amygdalin descends by the conducting 

 tissue of the bast and undergoes decomposition as it passes 

 downwards, yielding simpler products to the young cortex. 



