240 



FRANK R. LILLIE. 



Table II. 



Showing Rate of Loss of Fertilizing Power of Sperm Suspensions. 



we shall give the experimental data for 1/30,000 per cent.: 

 August 18, 1914. The eggs of two females were taken at 9.50 

 A.M. and washed at 10.04, 10.06 and 10.23 (150 c.c. of sea- 

 water being used in each washing). A series of 7 Syracuse 

 crystals was then laid out with 10 c.c. of sea-water in each. 

 To I was then added 5 drops of the egg-suspension. A single 

 drop of fresh dry sperm was then added to 333.3 c.c. sea-water 

 at 10.37 making a i/ioo per cent, sperm suspension, and i drop 

 of this was added to crystal i at 10.37.30 and stirred in by an 

 assistant making a 1/30,000 per cent, (i/ioo X i/io X 1/30) 

 sperm suspension in presence of eggs. One drop of the i/ioo 

 per cent, sperm was also added to crystals 2-7, which contained 

 no eggs, at 10.38, making 1/30,000 per cent, sperm suspension 

 in each. To No. 2, 5 drops of the same egg-suspension was 

 added at 10.40, to No. 3 at 10.42, to No. 4 at 10.46, to No. 5 at 

 10.54, to No. 6 at II. 10, to No. 7 at 11.42. At 2.30 P.M. my 

 assistant, Mr. Cohn, then estimated the percentages of segmented 

 eggs in each crystal, by first thoroughly mixing the eggs, then 

 assembling them, taking a sample, and making two counts of 

 100 each, which were averaged. 



The table shows (i) that the effect of time up to 64 minutes 

 is to diminish the fertilizing power of the suspensions at every 

 dilution represented. (2) That the rate of loss of fertilizing 



