162 



or varietal differences. Several of the disturbing factors of such 

 experiments are recognized in Balls's analysis. One excellent 

 point is that account must be taken of the number of seeds 

 planted in such experiments, rather than of the plants that 

 survive, for under adverse conditions only the hybrid plants may 

 survive, so that incautious experimenters might report very high 

 percentages of crosses. Indeed, Balls alludes to cases where only 

 the hybrids survived. 



One of the chief defects of modern Mendelian and statistical 

 methods is seen when the book is considered as a record of 

 botanical or biological observations. These methods often seem 

 to keep the student from becoming acquainted with his plants 

 or animals, doubtless because the numerical considerations absorb 

 most of his attention, and leave comparatively little for observa- 

 tion of other features. Thus we read of "the apparent identity 

 of all the modern varieties of Egyptian cotton in external appear- 

 ance," and "the absence of differentiating characters, excepting 

 for the lint itself," and other similar statements, which show that 

 the experiments did not result in the kind of familiarity with the 

 plants that is necessary for the most effective breeding work. 

 The extensive contamination of the Egyptian crop with the 

 so-called Hindi cotton also seems to have attracted very little 

 notice. The striking morphological features of the dimorphic 

 branches are passed with a casual reference. Of the same nature 

 is the following statement on page 147: 



"The Fi of Aegypto-Upland crosses is always a superfine 

 Egyptian. Thus, the mating of a 'bread-and-cheese' Egyptian 

 with a short-staple Upland gives a first cross bearing such lint 

 as is required by the fine spinner." 



It is true that such hybrids usually yield lint superior in 

 length and strength to that of the Egyptian parent, but it is a 

 mistake to suppose that the hybrid lint is of the same quality 

 as the Egyptian from the standpoint of the manufacturer. The 

 "fine spinner" always distinguishes samples of such lint from the 

 genuine Egyptian, and is more likely to take them for Sea Island 

 or for extra-fine qualities of long-staple Upland than to recognize 

 their Egyptian parentage. 



