THE RESERVE MATERIALS OF PLANTS. 485 



In other places than seeds large deposits of oil often 

 occur, though their purpose is not so obvious. We have 

 them in large amount in the pericarps of certain fruits, 

 such as the olive; in the petals of many flowers, e.g., 

 Funkia and Ornithogalum, in the leaves of some of the 

 Agaves, the roots of Oncidium, etc., etc. They can 

 hardly be regarded in some cases as truly reserve materials, 

 being perhaps more truly connected with the mechanisms 

 of dispersion. 



In places where their reserve character cannot be 

 doubted, it is interesting to trace the changes that take 

 place in them during the process of utilisation by the 

 young plant. In all the cases we have so far investigated, 

 but a slight change in the reserve material has been seen 

 to be necessary in order that a nutritive pabulum may be 

 prepared. The composition of an oil or fat is, however, 

 much more complex, and its decomposition accordingly 

 more intricate. 



The earlier workers in this field, noticing the constant 

 occurrence of starch in all germinating structures, seem to 

 have been led to the view that this form is essential to 

 nutrition, and that hence it must inevitably occur as a stage 

 in the decomposition of all carbonaceous food material. Even 

 in the digestion of oil this idea has been prominent. In 

 1859 Sachs (46) noticing the occurrence of starch in the 

 young embyro of a fatty seed, suggested that the oil was 

 in the first instance transformed into starch, though he 

 admitted that it was very surprising. In 1861 Peters (47) 

 endorsed the view of Sachs, publishing in support of it a 

 number of analyses of the oily seed and seedling of the 

 pumpkin during three stages of germination. 



More reasonable views, however, soon superseded this ; 

 in 1865 Fleury (48) working on the castor-oil, rape, and 

 almond seeds, pointed out a much more probable connec- 

 tion between oil and sugar, and showed that as the oil 

 disappears in germination sugar is to be found, and that 

 associated with the same events there is the coincident 

 appearance of a non-volatile acid. Von Hellriegel (49) has 

 argued in the same way with regard to rape seed, denying 



