204 



The J 



oiirnal of Heredity 



bolls, further out on the branch. 

 Shedding of buds is much less frequent 

 with P3g>'ptian cotton than with Up- 

 land varieties, l)ut in extreme cases 

 even the young fruiting l)ranches of 

 Kgyptian cotton ma\- abort, if the 

 plants are forced into rank growth. 

 That an o\er-luxuriant condition of 

 the plants ma>- l)e responsible for 

 shedding was indicated several years 

 ago in a paper that Llo\d seems to have 

 overlooked.' 



GENKTir I)I|-fi:ri:nci-:s in siii;i)I)I.\g 



These fads may be recognized with- 

 out prejudice to other causes of 

 shedding that Lloyd and earlier writers 

 have athancetl, including mechanical 

 injury, pests, diseases, drought, rain, 

 high-temperatures, and "root-asphyxi- 

 ation," by water-logging of the soil 

 in wet weather or in irrigated regions. 

 Llo\(l finds that shedding from me- 

 chanical injury is more prompt and 

 regular than from weevil attack. In- 

 jured buds fell off most frequently on 

 the second day, while weeAil-infested 

 buds had a maximum of shedding on 

 the eighth day. Lloyd advances a 

 theory of "competition between bf)lls 

 for water" to account for excessive 

 siiedding in brachytic varieties, but a 

 genetic factor is plainly indicated in 

 plants that abort all of their buds, 

 while their neighbors mature good 

 •'Sec "The .\l)()rtion of Fruiting Branches 

 Plant Fnduslry Cirr. 118, March 22, 1913. 



crops. Kgyptian cotton may retain 

 nearly all of its buds and young bolls 

 while Upland varieties in adjacent 

 rows are shedding nearh- all of their 

 buds. Sterile liybrids and sports, 

 including the so-called "bull-stalks" 

 of .Sea Island cotton, as well as unac- 

 dimatized or abnormalK- o\-ergrown 

 plants, may i)roduce small Hower-buds 

 in great numbers, but shed all of them 

 at an early stage, or a few bolls may 

 be set late in the season on secondary 

 stalks after complete abortion on the 

 primary stalk. 



In addition to determining the 

 jx'riods and rates of shedding of 

 squares and young bolls under different 

 conditions, Lloyd finds that "abscission 

 is inhibited during ^mthesis," meaning 

 that open blossoms do not shed, and 

 that rain destroys pollen and prevents 

 fertilizatifni. To this ma>- l)e added 

 that in cool, moist weather the anthers 

 sometimes fail to open, so that no pollen 

 is axailable. Complete failure to set 

 any bolls was obser\ed in 1905 in an 

 experimental planting of cotton in the 

 Senahu district of Eastern Guatemala 

 at an altitude of 2,600 feet, under 

 conditions of continuousK" high hu- 

 midity, with moderate, equable tem- 

 peratures. Although the plants grew 

 to normal size and produced many 

 flowers, the anthers remained closed 

 and the stigmas received no pollen, 

 in Cotton," I'. S. Dept. of .Agriculture, Bureau 



Tuic Risi\(; TiDK or 



Lothroj) Stoddard, A. M., Ph. D., 

 with an introduction by Madi.son 

 Grant. Pp. MO, with 3 maps. New 

 \'ork, ("harlcs .Scriber's sons, 1920. 



Ill a \ i\ id journalistic style. Dr. 

 .Stoddard has written an account of 

 world politics that deserves and will 

 probably get wide reading. He i)ic- 

 tures the |)re.sent world-wide donn'nion 

 of the white race, which cont-ols 

 nine-tenths of the glf)be, though it com- 

 l)ri.ses only a third of the inhabitants. 

 Ready to shake off tlie yoke are three 

 colored worlds. The jellow world 

 of Western Asia is the greatest im- 

 mediate menace, he believes, and he 



The Struggle of Races 

 Color, by thinks that the whites should respect 

 its position and gradualK- withdraw 

 from that part of Asia. riie brown 

 world, made up principalK of Islam and 

 the Hindus, also seems to him to be due 

 for independence, in the not distant 

 future. In the black world of Africa, 

 and the red world peopled b>- the 

 autochtones of the Aiuericas, lu- sees 

 little lu)pe for progress, and concludes 

 that the whites must control thi'se two 

 groups, if only to keep the >ellows 

 or browns from conc|uering them 

 and turning them against the whites. 

 The conclusion of the book, is a plea for 

 eugenics and an understanding of the 

 biological principles miderKitig the 

 organization of .societ\'. I*. P. 



