R KiDD AND C. West 223 



Some of the earliest workers to record results of experiments dealing 

 with the effects of removing part of the seed-reserves are Tautphoeus (35), 

 Marek(28), and F. Haberlandt(i8). These investigators worked with a 

 considerable number of annuals, including plants with albuminous and 

 exalbuminous seeds. They carefully cut off fractions of the endosperm 

 or cotyledons and sowed the seeds on damp blotting paper, but the 

 embryos were not provided with any artificial food-material. The 

 seedlings thus produced were compared with normal seedlings grown 

 under similar conditions^. The main facts which emerged from their 

 results were, that the life-duration of the embryo plant in the absence 

 of other food supplies was directly related to the amount of food- 

 material supplied from the cotyledons or endosperm, and that the 

 size of all the organs developed also bore a direct relation to the amount 

 of food-material originally available. 



The interesting implication of these early experiments, namely, that 

 the effect of the food-reserves of the seed on the early growth of the 

 embryo would continue throughout the life of the plant if the seedlings 

 were afterwards artificially supplied with nutrient salts, was followed 

 up by Wollny. In a series of experiments with peas grown in water- 

 culture solutions Wollny (41) first showed that the amount of growth 

 made by plants during the first month of development was directly 

 proportional to the amount of food-material originally available for the 

 embryo. The following table summarises the results of two of his 

 experiments: 



^ The question has sometimes been raised as to whether embryos which have been 

 completely deprived of their food-reserves immediately previous to germination are able 

 to develop at all. There seems to be no doubt, however, that if the requisite food be 

 artificially supplied in the form of simple substances, such as sugar and simple salts, 

 development can take place. 



Dubard and Urbain (9) reported that the endosperm was never indispensable to the 

 development of the plant. They suppHed embryos of wheat, oats, barley, JRicinus, etc. 

 with Knop's solution during their early stages of growth, and subsequently planted them 

 in ordinary soil and obtained mature plants. Brown and Morris (3) reared perfect plants 

 from excised barley embryos fed during their early stages with cane-sugar and mineral 

 nutrient-solutions, and kept in the light. 



With regard to exalbuminous plants, on the other hand, such as the bean, cauUflower 

 and savoy cabbage, Dubard and Urbain (10) found that they could not obtain development 

 under the same conditions unless the cotyledons were left attached to the embryo for a 

 period varying from 7 to 10 days, but Buckner and Kastle (4), who carried out experiments 

 with Lima bean embryos deprived of their cotyledons, found that while development 

 could not take place in the presence of salt solutions only, yet development became 

 possible if reducing sugars were supplied to the embryos. 



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