FIELD CROPS. 535 



ranging from August 28 to November 18. It is noted that wet cloudy weather 

 prevailed during the 10 days preceding the taking of the first samples. In 

 every case the first samples show higher starch percentages than the second 

 samples while the latter had higher moisture contents, except in the case of 

 the Fulleton Yam. Recalculation of the increased moisture to the moisture 

 of the earlier samples would not account for the decreased starch content, which 

 was in fact almost as great as the increase in water content. The author 

 suggests 2 reasons for this condition: (1) That at this period of rapid growth 

 some starch and sugar might be used in making cellulose of cell coverings, and 

 (2) that as cells rapidly increase their size their water content also becomes 

 greater. He also observes that the indications are that moisture content varies 

 with the stage of growth irrespective of rainfall, and that the upward tendency 

 of starch and low sugai'S continued until maturity or until freezing killed the 

 vines. On August 28 sucrose was high and glucose low, but as maturity ap- 

 proached sucrose decreased and glucose increased, although both starch and 

 total sugars decreased during the most rapid development. Later the starch 

 increased, but water and total sugars decreased. On November 18, however, the 

 sucrose was again high and glucose low. 



In 1909 the work was continued with Purple Yam and Pumpkin Early 

 Yellow Yam as sugary varieties and Polo and Brazilian as the starchy varieties. 



As a general conclusion from the 2 years' work the author believes that in 

 the immature potato sugar may be present either as glucose or sucrose, 

 depending upon meteorological conditions, and that sucrose is formed as a 

 product of the breaking down of starch as the potatoes mature. The 1909 

 crop grown on sandy soil was much higher in starch than the 1908 crop grown 

 on clay loam. "Where starch production is the object, if the plant is not evi- 

 dently mature, it should be dug immediately after the first killing frost, as the 

 highest starch percentage since the tubers have developed is then present. 



Experiments in crossing turnips, J. H. Wilson {Trans. Highland and Agr. 

 Soc. Scot., 5. ser., 23 {1911), pp. 18-31, figs. 8). — In a cross between the purple- 

 top Swede (seed parent) and a yellow turnip, it was observed that there was 

 a smaller number of seeds in the capsules than in those resulting from the 

 fertilization of the Swede by its own pollen. The seeds " were distinctly 

 smaller, being virtually like average turnip seed." 



When the hybrid seedlings developed, new characters in leaves and bulbs 

 evidenced the success of the experiment. Twelve bulbs resembled closely the 

 yellow turnip while 6 were purple-top. The neck was very short if present at 

 all. The author attaches much significance to the pi'esence " of irregular 

 swellings on the roots and at the bases of the bulbs of certain of the plants, 

 these swellings bearing a considerable outward resemblance to finger-and-toe 

 disease." 



The flowers of the hybrids were intermediate in character and a very large 

 proportion of the pollen grains were misshapen and abnormally small. The 

 capsules were undersized and apparently absorbed only a small part of the 

 lesources of the plant, which used its reserve energy " in the development of 

 a successive series of fine twigs, the latest of which were quite green and 

 bearing flowers when the earliest capsules were ripe and the shoots that bore 

 them were dead and dried." 



Irregularity in fruiting and serious deterioration in the form of the bulbs 

 was observed in the second generation. The more closely the hybrid resembled 

 the turnip the more liable it was to malformation by the counterfeit finger- 

 and-toe disease. The author describes the second generation plants in detail 

 and expresses the opinion that there is " little likelihood of such a strain as 



