Oct. i, 1920-Mar. is, 1921 



Illustrations IX 



33> a— Plantation at Whitesbog, N. J., for the testing of blueberry hybrids. Page 



B— Four-year-old blueberry hybrid in full fruit 160 



34. The ordinary wild blueberry of New Jersey l6 ° 



35. Fruit of a selected hybrid blueberry l6 ° 



Injury to Seed Wheat Resulting from Drying after Disinfection 

 with Formaldehyde 



Text Figures 



1. Graph showing rate of evaporation of paraformaldehyde at room tempera- 



ture, approximately 20° C • • • • 222 



2. Graph showing the relation of humidity of the air to percentage of germina- 



tion of stored seed in first experiment • • • • 226 



3. Graph showing the relation of humidity of the air to percentage of germina- 



tion of stored seed in second experiment 22& 



4. Graph showing the relation between humidity of the air and seed injury 



as indicated by rate of growth of germinated seedlings 229 



5. Graph showing the diminution in the rate of evaporation of paraformal- 



dehyde inclosed in a desiccator of 2,400-cc. volume 232 



Plates 



36. A.— Post-treatment seed injury occurring when wheat is dried after treat- 



ment with a 0.1 per cent solution. B .—Germinating seedlings of Little 

 Club wheat, showing characteristic post-treatment injury when seed is 

 treated with a 0.1 per cent solution 2 44 



37 . A.— Pots showing germination of treated seed stored for 32 days after dis- 



infection with a 0.1 per cent solution of formaldehyde. B.— Wheat 

 plants grown in soil from seed stored for 60 days after disinfection with 

 a 0.1 per cent solution of formaldehyde • • 2 44 



38. A.— Wheat seedlings showing injury produced by allowing the seed to lie 



in dry soil for 30 days after treatment with a 0.1 per cent solution of 

 formaldehyde. B — Desiccators with different degrees of atmospheric 

 humidity obtained by the use of mixtures of sulphuric acid and water in 

 different proportions 2 44 



39. Germinating samples of wheat stored for 35 days after treatment in the 



desiccators shown in Plate 38 B, illustrating the relation of seed injury 



to humidity -• • 224 



40. Varying injury to wheat treated with a 0.1 per cent solution of formalde- 



hyde, and stored in sealed bottles. A.— Sealed immediately after treat- 

 ment, 100 per cent germination. B.— Sealed after drying 7 hours, spread 

 on towels in laboratory, no germination. C— Sealed after drying 24 

 hours, spread on towels in laboratory, no germination. D.— Sealed after 

 drying 3 days, spread on towels in laboratory, 14 per cent germina- 

 tion 244 



41. Germinating wheat kernels, showing the prevention of post-treatment 



injury by washing the seed with water immediately after treatment. 

 A.— Treated with 0.2 per cent solution, which was not washed off before 

 drying, 32 per cent germination. B.— Treated with 0.2 per cent solution 

 which was washed off before drying, 76 per cent germination. C— 

 Treated with 0.1 per cent solution, which was not washed off before 

 drying, 52 per cent germination. D.— Treated with 0.1 per cent solu- 

 tion, which was washed off before drying, 74 per cent germination 244 



29667°— 21 2 



