August, 1911.] 



167 



Miscellaneous. 



5. The percentages of calcium aud 

 magnesium in the total plant were not 

 greatly different at the several periods 

 of growth. The calcium at maturity is 

 stored largely in the leaves, while 

 magnesium migrates to the grain. 



6. The hydrolisable carbohydrates 

 vary inversely with the percentage of 

 nitrogen absorbed. 



7. The rice plant contains a high 

 percentage of nitrogen, phosphoric acid 

 and potash during early growth, which 

 percentages become gradually reduced 

 during later development. 



8. Seasonal variations greatly influ- 

 ence the growth of rice, and likewise 

 produce noteworthy differences in the 

 composition, especially during early 

 growth. 



9. The rice plant, by the time it is 

 two-thirds grown, has normally taken 

 up about four-fifths of its maximum 

 nitrogen and phosphoric acid and nine- 

 tenths of its potash, and therefore fer- 

 tilizers should be applied before planting 

 or at an early period of development. 

 In common with other cereals, rice 

 demands readily available plant food in 

 abundance during early growth. 



10. Rice can take up what may be 

 looked upon as an excess of nutrients if 

 these be present in sufficiently large 

 quantities. 



11. There is no return to the soil through 

 the roots of rice of nitrogen, phosphoric 

 acid, or potash, and any loss of these 

 substances that this plant may sustain 

 is most likely traceable to the leaching 

 action of rains and dews. 



12. Reducing sugars were found in 

 notable quantities in the rice plant at 

 all stages of growth and were greatest 

 at the first period. 



13. Sucrose, while present as a trace 

 at the first period, occurred in the stems 

 at the second period to the extent of 

 10"38 per cent. At maturity this had 

 been largely converted into starch. 



14. Starch gradually increases through- 

 out the growth of the plant, and at 

 maturity is stored very largely in the 

 grain. 



15. The pentose-forming bodies con- 

 stitute a large percentage of the carbo- 

 hydrates of the rice plant at every stage 

 of growth and reach a practical 

 maximum at the flowering stage. 



16. Cellulose occurs in large quantities 

 in all parts of the plant, except the 

 grain, and likewise almost reaches a 

 maximum at the second period. 



The above conclusions were drawn from 

 a study of two different crops of rice, aud 



while the experiments are preliminary, 

 the results should be considered as prob- 

 able, though not definitely settled. In 

 the near future the practical bearing of 

 these experiments will be set forth in a 

 publication of more popular nature. 



Work of the Entomologist. 



The most interesting feature in the 

 work of the entomology department 

 was the introduction and breeding of 

 parasites against harmful insects. In the 

 study of the pests attacking the cotton, 

 fruit trees, and legurninosce, employ- 

 ment of artificial remedies has been 

 found impractical, at least on a large 

 scale. 



For the first time in the history of rice 

 cultivation in the islands, this cereal was 

 attacked by Heliophila unipuncta, 

 serious losses having been reported from 

 all the rice producing sections, the 

 damage at two places amounting to from 

 ten per cent, to sixty per cent, of the 

 crop. 



Outbursts of army worms have been 

 reported from different rice-growing 

 sections of the Philippines. One species 

 has been found by members of the 

 Entomology class of our College, 

 attacking rice in Sta. Rosa, Laguna, 

 and in Sto. Tomas and Tanawan, 

 Batangas. Investigations already have 

 been undertaken to determine this 

 species. 



A synopsis of the Hawaiian Aphidae 

 has been prepared. These small insects, 

 although of great economic importance, 

 have received practically no attention in 

 the Philippines, as was also true in 

 Hawaii. The Entomology Department 

 there has realized their significance and 

 the synopsis was the result of their 

 work. A key to genera is given, and 

 also the descriptions of twenty-one 

 species, four of which are new. By 

 means of these descriptions it is hoped 

 that the Hawaiian farmers can easily 

 identify the insects when they see them. 



The Influence of Manganese on the 

 Growth of Pineapples. 

 (Press Bulletin No. 23.) 



In some of the pineapple soils in 

 Hawaii there are certain black spots 

 where pineapples do not grow success- 

 fully. In these spots the pines have a 

 wilted yellow appearance, and the 

 application of fertilizers and lime in con- 

 junction/with good tillage and drainage 

 Uas not resulted in effectually over- 

 coming the yellow appearance of the 

 pines. 



