1 9 14] 



CROCKER 6- DA VIS— DEL A YED GERM IN A TION 



301 



first slightly leads water in rate of elongation, but falls behind it 

 later. This slight early advantage can well be accounted for by 

 the variation in the embryos from employment of so few, while 

 the later falling behind water is undoubtedly related to injurious 

 effects of the acid. The N/6000 HC1 at first kept pace with water 

 but later fell behind it. 



TABLE VII 



Showing the elongation of Alisma Plantago embryos in water, 1/3000 mol. HCl, 

 and 1/6000 mol. HC1. 



Condition of the embryos 



Air dry 



1 hour in water 



3 hours" u 



6 « « a 



24 a u « [[[[[[ 

 72 a u u 



Air dry 



1 hour in N/3000 HCl 



3 hours * * * 



6 " « « a 



24 " " u " 



72 u " « « 



Air dry 



1 hour in N/6000 HC1 



3 hours" " u 



6 u « « u 



72 u u « 



Total length 



8ll 



899 

 996 



1080 



1208 



1967 



817 

 918 



I03S 



II02 



1 193 



I788 



IOO5 

 III4 

 1222 

 1312 

 1449 

 2I07 



Average length 



IOI.4 

 112. 5 



124. 5 



I350 



151. o 

 246.0 



102.0 

 114. 7 

 117. o 



137.7 



148.9 

 223-5 



100.5 



in. 4 

 122.2 

 131. 2 



144-9 

 210.7 



Percentage of in- 

 crease over air-dry 

 length 



10. 5 

 22.8 



33 2 

 49.0 



142.5 



12.3 

 26.6 



35-0 

 453 



119. o 



10.8 



21. S 



30-5 

 44.I 



109.0 



[I A summarizes two other sets of measurements 

 N/3000 and N/6000 HC1 on the rate of elongatior 



TABLE VII A 



Average percentage elongation for 10 embryos each in water and the HCl solution 

 mentioned. 



N/3000 HCl 

 N/6000 HCl 

 Water 



N/3000 HCl 

 Water 



— ^— * — -! 



i hr. 



2 hrs. 



3 hrs. 



4 hrs. 



IO. I 



16.9 



24.7 



28.9 



IO.8 



16.9 



23.O 



27.O 



9.1 



16.2 



21.9 



27.5 



II. O 



20.0 



26.O 



29.O 



10.0 



16.8 



24.7 



28.7 



5 hrs. 



32.O 

 30.O 

 30.6 

 32.O 

 31.0 



