12 



BULLETIN 1255, U. S. DEPARTMENT OF AGRICULTURE. 



Table 5 contains a summary of the data in Table 3, and Table 6 a 

 summary of the data in Table 4. The probable error of the average, 

 the combined average, and the combined probable error, were calcu- 

 lated by using Mellor's formulas (3). 



Table 5. — Average composition of strains of Eureka lemons (Table 8). 



Date. 



Number 

 of trees 

 sampled. 



Number 

 of fruits 

 analyzed. 



Specific 

 gravity. 



Rind. 



Acid in juice. 



EUREKA STRAIN. 



1920: 



2 



6 

 11 

 5 



30 



189 

 303 



145 



0. 948±0. 0014 



. 927± . 0011 

 .901± .0006 

 . 956± . 0005 



Per cent. 

 47. 1±0. 84 



36. 9± . 17 

 42. 4± • 11 

 33. 4± . 17 



Per cent. 

 5. 31±0. 024 



1921: 



4.60± .020 



June 



5. 05rh . 007 





4. 43± . 019 













. 932± . 0003 



39. 1± . 08 



4.96± .006 











SMALL OPEN STRAIN. 



1921: 



6 

 2 



127 

 65 



.910± .0011 

 .961=b .0009 



42. l=fc . 23 

 34. 6± . 33 



4. 80± . 014 





4. 62± . 038 







Combined averages 







. 939± . 0007 



39. 6± . 19 



4. 78± . 013 











SHADE TREE STRAIN. 

 1920: 



5 

 5 

 6 



78 



165 

 155 

 159 



. 961± . 0006 



. 926± . 0010 

 . 925± . 0008 

 .948± .0006 



51. 4± . 30 



37. 7± . 21 



42. 6=fc . 21 

 35. 3± . 19 



4. 64± . 017 



1921: 



4. 58± . 017 





4. 67± . 014 



November 



4. 49± . 019 







Combined averages 







. 945± . 0004 



40. 4± . 11 



4. 61=b . 008 











DENSE UNPRODUCTIVE STRAIN. 



1920: 



Jnnp 



4 



6 



7 

 5 



62 



220 

 150 



156 



. 958=fc . 0014 



. 925± . 0012 

 . 929=h . 0009 

 .946± .0005 



51. 2-b . 10 



38. 3± . 23 

 40. 3± . 14 

 34. 2=h . 17 



4 84± .024 



1921: 



February 



4. 37± . 010 





4. 73± . 013 





4. 47± - 014 













. 934± . 0004 



44. 3± . 07 



4. 52± . 006 











