24 HARRIETT M. ALLYN. 



TABLE I. 



AGENTS INDUCING THE FORMATION OF SWIMMING LARV/E^UNSEGMENTED EXCEPT 

 IN THE CASE OF HEAT, OR OF KCL FOLLOWED BY 



OXYGEN EXCESS IN THE SEA-WATER. 

 Potassium chloride, 2 J^ M in sea-water. 



0.5 per cent. 10^ minutes to 5 hours and 10 minutes, 

 i.o per cent. 3 minutes to 5 hours and 10 minutes. 

 2.0 per cent. 21 minutes to 3 hours and 10 minutes. 

 3.0 per cent. 45 and 60 minutes. (Shorter exposures not made.) 

 3.5 per cent. i minute to 3 hours. 



4.0 per cent. 45 to 60 minutes. (Other exposures not made.) 

 5.0 per cent. i minute to 3 hours and 10 minutes. 

 6.0 per cent. 45 and 60 minutes. (Other exposures not made.) 

 7.5 per cent. 5 minutes to 4 hours. 

 10.0 per cent. 5 minutes to 3 hours and 58 minutes. 

 15.0 per cent. i minute to 31 minutes. 

 nfio acetic acid in sea- water. 

 i.o per cent. ioj^ minutes. 

 5.0 per cent. 5 minutes. 

 Low temperature. 



9.5 C. i hour or 2 hours and 17 minutes. 

 12.5 C. 2 hours and 17 minutes. 

 Oxygen-saturated sea-water. 



1 hour to 2 hours. 



De-aerated sea-water (after 2 per cent. 2 }/% M KC1 3 minutes) over night. 

 De-aerated sea-water (with 2 per cent. 2% M KC1) i hour and 30 minutes. 

 Alcohol in sea-water. 



S per cent. 40 minutes. 

 High temperature. 



33-34 C. 25 minutes to i hour and 30 minutes. 



32.5-34.5 40 minutes to i hour and 30 minutes. 



30-30.5 40 minutes. 



33-5-34-5 25 minutes to 40 minutes. 

 Sodium chloride, 2 }^ M in sea-water. 



I 3-7 P er cent. 5 minutes and i hour and 10 minutes. 

 2]/2 M sodium chloride and n/io sodium hydroxide, in sea-water. 



8.0 c.c. NaCl + 50 c.c. sea-water +0.2 c.c. NaOH 20 minutes to 18 hours. 



8.0 c.c. NaCl + 50 c.c. sea-water + 0.4 c.c. NaOH 20 minutes to 18 hours. 



8.0 c.c. NaCl + 50 c.c. sea-water + i.o c.c. NaOH 50 minutes to 18 hours. 

 M/IO hydrochloric acid in sea-water. 



2 per cent, permanently. 



Fatty acid followed by hypertonic sea-water. 



w/io butyric acid 2.8 c.c. + 50 c.c. sea-water 2 minutes; then 200 c.c. sea-watei 



20 minutes; then 8.0 c.c. 2% M NaCl + 50 c.c. sea-water 30 minutes. 

 Potassium chloride followed by hydrogen current through sea-water. 



3.5 per cent. 2% M KC1 in sea-water 45 or 65 minutes, then hydrogen 3 hours. 

 Potassium chloride followed by excess of oxygen in sea-water. 



3.5 per cent. 2^2 M KC1 in sea- water until after formation of second polar body, 

 then oxygen saturated sea-water 30 min. to 4 hours. 



